I created numerous surveys for field collection using the Design tab in the web application. We collect data using the app on iPads. These forms have worked well and we have collected hundreds of records. In recent days, when I access Survey123 online to access and analyze our data, I get an error that says "Survey does not exist or is unavailable" even though I know the survey exists and sometime I can see the number or records each of our survey has. This problem comes and goes, and sometimes we are able to access our data. Thanks for any help.
Could you check this post to see if the synopsis applies to your case?
If so, we had addressed this in the hotfix:
Please let us know if the hotfix does address your issue.