Upload Files with UploadSet in Cloud Foundry

Hello Guys,

we are using UploadSet in our FIORI app to upload files as GOS documents to some Business Object. We therefor use an AttachmentSet in backend which works with CREATE STREAM method. This works fine as long as we are using BAS local and classical launchpad url. But when deploying the app to our BTP Cloud Foundry Build Workzone launchpad upload does not work. We are getting POST error "ERROR_HTTP2_PROTOCOL_ERROR", backend method CREATE STREAM is not reached. So is there any special thing that has to be considered when using UploadSet in Cloud Foundry?

Regards
Michael