0.9 mBTC is equal to $39.15 if bitcoin is $43500. That is too high. What can likely case in if if you have many inputs or outputs in that transaction.
If you are having many UTXK count, which will lead to high inputs if you want to make transaction (like consolidation), the transaction fee will be very high. The best is to wait for the mempool to become less congested before making such transaction. Like if you are lucky and the mempool go less congested that 1 to 2 sat/v ye transactions can get confirmed again.