I returned to work for a company because my former boss reached out to me. I have no complaints about the pay, but I work like a dog. However, at times I feel my boss is somewhat unfair to me. I’m in charge of more than three departments; when I arrived at the store, everything was a mess—standards, cleanliness, merchandise, and so on. I’ve been making gradual improvements, but I don’t have a dedicated team to whom I can delegate tasks.

Have you considered the possibility your boss pushed you to come back because she knew she could lean on you hard without pushback from you?

In most cases when old bosses reach out to former employees it’s because they are struggling big time and remember you as a strong employee. Seems to be the case. You can talk to them and express yourself that it’s too much work. They may discuss a slight pay decrease and/or hiring an assistant or more subordinates to help. You can think about whether or not it’s worth it for you at that point but it sounds like you’re holding all the cards because as I stated they might be a little desperate. The key is that you need to express yourself professionally, calmly and factually.

May I ask a few questions please?
1. What tactics have you used to improve and motivate your team?
2. Who up the ladder have you reported this to?
3. Have you initiated? Any first step discipline & how many times have you had to ask?
At the risk of sounding rude my answer is
Give up! Your not going to change there work ethic and nothing or nobody will get them working as hard as you, soz as the kids say your first mistake was in your own words YOU (I)have been making improvements??!! Well done and carry on BUT you are going to be on your own why? Here’s my 10c answer to what happened
Your friend their boss brought you in to “fix”all the mess? The mess left by your other staff yes?
Here on the job site yes? There are so many other scenarios but in a nutshell they don’t like you they obviously don’t respect you and why should they lift a finger to help? Your here saving the day congrats your their modern day martyr why should they help? Have you asked? Have you delegated tasks? Have you issued warnings? I’m not saying this to offend you, I know You’ve
had good intentions but it’s backfired. My discounted 2c advice Always approach every new work environment with your head held high, confident get to know your new team ask questions,Who is responsible for what start there build rapport and workships build trust and earn respect.

Literally I had the SAME scenerio. Former Boss reached out. Hired me back to replace a "Bad Store Manager!" Place was a train wreck! The 3 Assistant Managers all but gave up under the Bad Manager. Building trust and relationships while trying to rebuild the TEAM morale took months, before we could even try to tackle the physical store issues.
There were associates that welcomed me with open arms. I had either worked with them in the past, or they heard about my work ethic from others.
There were nay sayers, that ​had attitudes that "Nothings going to change", or "she can try doing overnights to fix the stockroom, but we've already done that, and its back to a mess!"
I had dept Coordinators who would work side by side with me, doing projects and overnighters, because they just "Wanted Direction and Leadership!"
Then, unfortunately there was 1 Assistant Manager, who despite my good intentions, they were either jealous of my "coming back!" OR they wanted the promotion, They were super defensive that I was there, making improvements. Which somehow in their minds, I was showing them up or blaming them for the deteriorating state of the store. NOT TRUE. I'm
very sensitive dealing with people's feelings while trying to make a team, make improvements, while not stepping on egos of some.
The one Assistant decided that everytime another Assistant was on vacation, that she "got sick!"
Three times, left me holding the bag. Never held accountable by the Bad Manager. So I addressed it first with the Assistant and after 3rd time I went to the District Manager.

MY ADVISE TO YOU;
1) Over Communicate with your District Manager. She reached out to you and hired you knowing she could count on you. Yes, she maybe hard on you, and pay you 2 people's salary. But you knew it was going to be a long haul going in.

2) Build your core management team. Daily and weekly team meetings with your managers. Clear concise direction and goals. Then repeat the same with management and their dept Coordinators.
Being on the same page and same goals is half the battle. Making them all feel included on running their depts gives them incentive to be present, taking ownership, giving them pride.
Although donuts and lunches do incentives some, RESULTS are the tastiest rewards. Cheerlead by working with them side by side....Getting RESULTS is what will earn their respect.

3) Give yourself some Grace. Rome wasnt built in a day. Rebuilding a team and rebuilding a broken store does take time. Take the pressure off yourself.
Your inner voice is saying
" All eyes are on me to fix things!"
THROW THAT OUT THE WINDOW. Yes, your boss maybe hard on you, and demand more from you. IF you feel like you're getting beat up verbally by the boss, you need to have a conversation, letting them know that you are doing your best. That they are coming off a little aggressive. Maybe it wasnt their intention. They won't know you are having difficulties with their style of managing you, IF YOU SPEAK UP!

Two things are possible here. 1 your manager is overwhelmed with his position or situation and needs help. 2. He is taking advantage of your skillset as he knows what you can do. Either way you need to have a conversation and express your feelings. Maybe they don't know what you are experiencing or they don' care as they are trying to save their job. Either way you need to find out and make an informed decision how to move forward. Good luck!

For instance, she constantly reminds me that she pays me very well—literally paying me for two people's worth of work. We have a credit card sign-up goal at the store; whenever I’m the Manager on Duty (MOD), I help out at the register, motivate and coach the associates, and handle everything myself without needing to call on anyone else. For some reason, I don’t always hit my credit card goal, but that isn't entirely up to me; it depends on the associates and having the right customers. At this point, I feel very frustrated.

You would have to start developing a team yourself. I know it can be tough from experience.

You are the team sadly I’d ask for a salary and position change or leave and let them burn it’s what he’s setting himself and you up for👍🏻

I did that 8 years ago too. but now i regret it.

You said the old boss hired you back. Wanted you back. He needed your back. He sees something in you that maybe you don't see. You're a strong person that can fix these problems. He needs you