Hi Mohamed,
I got the same error too and fixed it by choosing a 16-char key and updating the value twice for the encryption key for 32-char and the same 16-char for the legacy encryption key. Below is an example:
EncryptionKey – ABCD1234EFGH5678ABCD1234EFGH5678
LegacyEncryptionKey – ABCD1234EFGH5678