App promotion image ad template causing UNEXPECTED_INTERNAL_API_ERROR

Hi, i've been trying to create App promotion image ad by using TemplateAd, but all my attempts lead to UNEXPECTED_INTERNAL_API_ERROR. I tried different images but nothing helps. I have simple campaign for display network with country and os targeting. What am i doing wrong? request+response

App promotion image ad causing UNEXPECTED_INTERNAL_API_ERROR. Is it working as intended?

Hi, i've been trying to create App promotion image ad by using templateAd with simple campaign on display network with country and os targetting. All my attempts lead to UNEXPECTED_INTERNAL_API_ERROR. Maybe App promotion image ad is not supported? SOAP request and response https://gist.github.