An item with the same key has already been added

I’m trying to download bank statements in csv format for the first time and keep getting this error message

An item with the same key has already been added.

Probably best if you could email bank statement file you are trying to import to lubos@manager.io. I will try to reproduce the issue.

I tried twice to email you the statement but got the below error

Sorry, the file you are trying to upload is not authorized (authorized extensions: jpg, jpeg, png, gif, manager).

it is definitely a csv file

It sounds like you tried to upload the file to a forum message. You need to send it as an attachment to an ordinary email.