Companion: token.verify.error Error: Invalid encrypted value

I am trying to set up Uppy/Companion, exporting env variables including Facebook.
When I click on the Facebook icon, the connection to Companion is being established, but I always get a 401 error.

companion: 2020-09-24T22:04:39.142Z [error] 522b3352-9458-4f9b-8e31-37ba0e5d8f93 token.verify.error Error: Invalid encrypted value. Maybe it was generated with an old Companion version?

According to
./node_modules/@uppy/companion/lib/server/helpers/utils.js at line 152
encrypted is “null”

Can anybody help?