I have created a feature class with Global IDs and enabled attachments. I have also created a table that would capture additional details and set a relationship.
I published this in our portal and at the time of creating a survey from this feature service it does not pull the related table to enable the repeat on.
Can I achieve repeats on a feature service created form?
Did you publish the layer as a Hosted Feature Layer or a referenced non-hosted Feature Service? If the latter, is it in an enterprise geodatabase?
There are several additional requirements when creating the service yourself (i.e. not using Survey123 Connect and Hosted Feature Layers).
It's very likely the situation you are encountering is to enable 'supportsApplyEditsWithGlobalID' property. You also need to ensure that all layers, including the parent layer and related tables, have globalid fields. I can see you have the relationship key 'parenrowid'. Personally I'd just follow the default Esri one and have 'globalid' and 'parentglobalid' as guid fields across all tables and use these for the relationships.
I'd recommend going through these two blogs:
And also noting the limitations here:
A lot of the limitations that still allow you to publish really come into play when working with enterprise and non-hosted services. Not necessarily what you are seeing here, but strongly recommend being on top of them.
If you are still stuck - let us know how far along you get, and maybe share more information if you can around how things have been set up 🙂