OData in Sandbox

I am trying to consume a published OData service from an app in the Sandbox. I have seen this working before, but I can't seem to get it working. The settings in the Modeler are the same (except for the entityname) and the version is also the same (5.19.0). I guess I am missing a setting somewhere, so I am hoping someone can give me a pointer in the right direction. I have followed each Mendix guide I can find, but none of them mention the Sandbox. What I have done so far is create the service, select one entity to expose and set the allowed roles. By doing this the service should be reachable via https://>appname<.mendixcloud.com/odata/CRM/Relation/ or at least visible at https://>appname<.mendixcloud.com/odata-doc/. None of these work and both return a 404 error. Trying to import data into Excel I get the following message: "We couldn't access the data feed server because the feed URL is invalid.". Input is very much appreciated!
1 answers

After consulting Mendix there was no real solution to my problem. What fixed it though was exporting the entire project and importing it in a new project.