Can't make a backup to S3

Hi guys!

I created a backup configuration to AWS S3.
All of my backups failed because “malformed secret, incorrect access and secret key”.
I verify multiple times that my access and secret key are correct and base64 encoded. I inserted them through Rancher’s UI (Which made the encoded automatically).
In addition, I succeeded to use this key and secret from other tools like Cyberduck and edit the specific bucket.

Any expert that have an idea what am I missing?
Thanks in advance!