The 'Service invoked too many times' error is triggered when a Google Service cannot be used because the user hit his daily quota. This article explains further this issue.
Why do I get this error?
Form Publisher uses Apps Script services to run, and it imposes daily quotas and rigid limitations on some features. If you exceed a quota or limitation, the add-on will no longer be usable by the current user.
Apps Script quotas are shared with every other Scripts and add-on, so even if it's the first time you use Form Publisher this day, it's possible that you still already have burnt your quota. (List of quotas)
What should I do?
To solve that, try again as soon as your quota resets because we have no control over them.
warning As a reminder from our Terms of Use, "Form Publisher is strongly linked to the infrastructure provided by Google. Changes by Google on this infrastructure might change the product and the features we can provide." Please understand that we cannot solve this issue as this is not from the Form Publisher side, but Google. If the problem persists and occurs many times, the best thing to do is to retry later.