Error connecting to Paratext project

[cdfarrow]

I've just updated to v4.3 and am getting this error when I try to choose the Paratext project (both in the Paratext Integrations settings and the Sync to Paratext step):

It worked after logging out and trying again yesterday, but today I got the error again when checking the configuration to Pull from Paratext.

Note that I have two Paratext projects with the same language code, and it seems to keep switching back to the wrong one.