Bittrex has gone downhill after they removed legacy accounts.

They are super tough with KYC and if you aren't willing to provide whatever they ask you to (and this includes proof of income, source of funds, etc.), then you shouldn't use them whatsoever. Stick to Binance, and even then as it is a CEX there is a certain degree of risk.

All you can do rn is to comply with whatever conditions and requests they give out, and be patient. Their support team definitely is not the best so you need to give them some time.