Is there a way to get today's action corrected?

You could file to reconsider and/ or appeal.

Yes absolutely. You should hire an attorney to file and quash the active warrant.

Can a landlord back out of a lease less than a month before we move in because the current tenant decided to stay?

You cannot force them to do anything. If the previous tenant holds over the landlord could begin the eviction process which typically take 6-8...

Can I sue the USPS?

You can. It sounds like a tough thing to prove. You have the burden unfortunately.

How can i get an eviction removed from my record when it doesnt show up on my credit report but it shows up on rental history?

You would have to file a motion to shield the case.

The apartment complex I have lived in since 2018 denied me a transfer to a apartment within my complex based on a car accident.

Unfortunately they are not obligated to transfer you. Just like you are not obligated to renew your lease. It seems there is more going on then...

Can a new apartment management collect on past due rent owed to the old management ?

Yes.

Can a Property Management Co. enter a rental home 2 or more times a month?

This seems unreasonable however your lease would control. Have an attorney read the lease.

Messages between a minor and myself when I was unaware of her age?

I would agree. Stop posting facts. Make a free consultation to talk with an attorney. Do not speak to Police without consulting with counsel.

Do I have to pay the balance on a security deposit withholding form that was sent to me after I moved out?

As counsel stated you are not required to pay. If you contest the amounts then respond in writing. Request documents of proof.