SaltyTank and Codebard, I hope this finds you well.
I ran into the same issue last night. Thus searching the forums for answers/
I tried a few of the options seen in a couple other posts, to no avail.
So, I built a test site in sandbox and applied the plugin and connected, then worked. Curious.
So, let’s try this in production:
I went into the plugin and removed my connections, but also went to https://www.patreon.com/portal/registration/register-clients and removed my connections.
Logged out of wordpress, logged out of patreon, logged back in respectively, loaded the plugin configuration and ran the connection wizard. I was asked to recreate the oauth.
This just worked for me.
What did NOT work for me, was building a new client api manually and updating the information in the plugin manually. So, what it looks like is the edit function is not working to initiate the handshake, like edit and reconnect. But the “New Start” wizard does still seem to work.
Not a full fix but a duct tape and bandaid solution.
I hope this works for you too!
WP 5.5 PHP MySql 7.2 and running on SSL and Hostgator.