I tried calling out of work on Friday and no one picked up the phone until a store manager called me at 9:30a.m. saying if I have covid I need to go to the doctor and told me I can't come back until the 28th.
He probably termed you. You need to go to a place to get covid tested and present them the paper work. The policy is still 5 days quarantine. Then come back. You can't just keep calling out. Every store is different on attendance policies. You will need to file a union grievance to remove it. Most likely your manager fired you for job abandonment. That's not how it works. They would of verbally warned you or suspended you first.
Covid is now just a regular cold and most don't even quarantine any more. Nor wear a mask. Or wear a mask correctly.