Hi,
Thanks for raising your concern.
My apologies for the delayed response as I discussed your issue to the rest of the team.
If you will create HTML5 using
MediaService, you should use the created media bundle to the
Media type object of
AdGroupAdService not as an
Asset type and vice versa as they are two different types.
Let me know if you have further questions.
Regards,
Ejay
Google Ads API Team

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