Citibank review: High yield savings account

I opened a new high yield savings account with Citibank online on Oct 2. My spouse and I have held MasterCards through Citi for 10+ years spending on average of $2k/month thru the accounts and never had a missed payment or late fee. We attempted to deposit $10k to this new savings account via an ACH from our longtime checking account with TD Bank on Oct 4. The deposit failed because Citibank had the TD Bank coded as a savings account instead of a checking account. After resolving the coding at Citibank, we attempted an ACH deposit of $1000 from TD Bank to the new Citibank High Yield savings. While awaiting the ~5 business days for that transaction to clear through the bank systems, we used the Citibank app on our mobile phone to deposit 2 checks on separate days from an inheritance distribution on Oct 12 and 13. (The Payor of these checks confirms those checks were cleared to Citibank on Oct 13.) Within a day or 2 we noticed we could not log into the account from the web or from the app. We received a letter for each inheritance check (each