The bot only reads one mail and finish "successfully"

I have a process that involves reading unread mails from a specific mail folder, the problem is that the loop (for each unread mail in mail box) is supposed to do something with each unread mail, but the bot only reads one mail and finish "successfully" as if in the folder there was only one mail but it is not like that.

I did the following test just to verify that it was not a coding error and the bot still only reads one email in the specified folder even though there are more.

NOTE: Previously it was working properly and then it just stopped working as it should.