I created a survey form from my feature service. I went to add a field in the XLSForm and it will not publish because of the error in the picture below:
I have not done anything to the original feature service and have not moved any of my files into different folders since the beginning. One day it just wasn't working anymore. I don't want to have to redo this survey since its linked to my WebApp so I hope there's an answer!
If the hosted feature layer was created as part of the survey publish process, the same warning would appear but you would have the option to add the missing field.
This survey uses a custom service URL, meaning we targeted an existing feature service instead of creating one as part of the initial publishing process. As Survey123 didn't create or 'own' the hosted feature service on creation, you will need to ensure the target service URL has the necessary fields for the questions in your survey.
In short you'll need to add a field to your feature service manually, as it is a custom service URL.
Thank you Chris! That worked for me and the survey was able to publish. However, I ran into a new issue.
When I try to save the feature service after I add the new field, it asks me to save it as a new web map. Since my form is already tied to my current web map, I don’t want to screw things up by saving the service as a yet another map. I just have kind of been exiting out the AGOL tab once I make changes and it seems to save but I’m not sure I should be doing this.
Table changes such as feature edits or adding fields will commit to the hosted feature layer.
It sounds like you have added the field and are then trying to save the Web Map. You don't need to save the Web Map here as the field has been committed to the hosted feature layer.