Sorry to hear this, but I have a couple of thoughts.

1) Don't know what your handling time is, but I moved mine up to 15 days to give me a massive buffer in case of delays. I didn't have a single item that ended up being late. You must have had a large number of those to increase your defect rate and put your account at risk. Ebay cannot help you if you over-promised and under delivered in a pandemic.

2) Ebay customer service is atrocious, but Amazons is just as bad if not worse. Before you jump on board there, I highly suggest you spend several days reading the forums which have some excruciating stories that make Ebay seem like a kids lullaby in comparison. 

3) Amazon can and will shut you down and withhold payments at a whim, with no help or explanation given. You have to be super focussed on your metrics and be prepared to shell out higher fees in general.