@Aadako I've had the same issue many times. I tried to fix the same workflow you linked to, but even after trying the various things that *should* have fixed it, ran out of time.
I went and fixed the original Dropbox workflow—which I think Ryan forked from—which is a much simpler codebase. I submitted the change as a pull request to original author, but you can get the working version in the PR here. That original workflow doesn't have the option for expiring 7 day links, but it does the job for the basic need which you and I share of quickly getting Dropbox file links for our own use.
If you want to just edit it yourself, find the file `register-db-auth-token.sh` in the workflow folder of Uri Cohen's "Copy Dropbox Link" workflow. On line 2, change the
grep "HTTP/1.1"
part of the line to
grep "HTTP/2"
then save it and you should be all set.