Issue when reponding to form inquiries

Recently set up email forms for a client. When the client tries to reply to the customer in Outlook she is getting this error message: "You are not allowed to send this message because you are trying to send on behalf of another sender without permission"

We were using a different contact form service until just recently and this was not an issue. We switched to Jot Form because of the integration with email marketing systems like Constant Contact and iContact.

How can we resolve this issue?

The issue might be with your sending permission with outlook.

https://docs.microsoft.com/en-us/previous-versions/office/exchange-server-2007/bb123879(v=exchg.80)

Related article:https://community.spiceworks.com/topic/351233-send-as-issue-in-exchange-2007-outlook-2010

Tested a sample form with my outlook account but I can't seem to replicate the issue at my end. I was able to reply to the notification email.