Is Magic Eden still a safe place to sell NFTs? I get this warning and all transactions are failing

I’ve been away from crypto for over a year but recently looked through some old wallets and realized I have some NFTs worth a few hundred bucks. I first tried selling them through the instant sell feature in the solflare wallet and that didn’t work so I went to ME and it gives me this warning.

My questions are: 1. Why would I have to worry about a transaction on ME? I never had to in the past. 2. How much SOL do I need for transactions to go through because I had about $4 worth of dust in my wallet but all of them failed and now I have .37 cents. SOL transactions used to be a fraction of a penny if I remember correctly.