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Sounds like a plugin conflict. Were you able to replicate this on a clean WP + s2Member installation?
https://s2member.com/kb-article/testing-in-a-clean-wordpress-installation/

https://s2member.com/kb-article/common-troubleshooting-tips/

It definitely is a plugin conflict. I’ve used s2 memeber many times and it is up to date. I know its my plugin that is conflicting but I can’t seem to track down the conflict. I was wondering if other have had this issue. I can’t seem to track it down and I have never seen this issue before.

Maybe someone will able to help you if you provide more details about the errors you receiving, which plugin is conflicting with s2Member and the steps you took to replicate the issue.