Work Told Me I Can Work Remote, Now Say No And Want Me To "voluntarily Terminate"

I got a letter from my immediate boss saying I can work remote back in July because I was moving out of state.

I went on maternity leave end of August and am now returning to work but remotely. Boss and his boss along with HR are saying I need to quit or voluntarily resign.

What can I do with the above?

Additionally, during this time im getting payment from EDD for PFL as well as my company "making me whole" when needed. Well they messed up my pay and over paid me during 2 instances (one of which i fully understand I have to pay back because I didnt have anymore PTO and/or paid leave, the other is very confusing and still need to figure out why I owe this, btw they messed up both of my other maternity leaves as well and I had to backpay them a little every check) They are saying i owe back 6k and have held my previous check of 5k.

Are they allowed to hold my full check without agreeing to some form of repayment?
I've requested a breakdown of how they got to me owing them back 6k and they are all confused on the numbers as well. I know about 4k should go back but they kept the whole 5k check, I havent been paid in over a month.

What can be done for both issues?

Edit: In the US, from CA to VA