Hi Lourby,
Thank you for giving us the chance to assist you with your iPad Air. You can count on us to do our best to assist you or get you pointed in the right direction.
We understand that you are experiencing issues mirroring your iPad screen when using Spotify, Netflix, and other streaming apps.
We'd like team up with you and perform some steps to isolate the issue.
We recommend updating your iPhone if you haven’t. While it isn't inherently assured that an update will resolve the issue, updating to the latest version of iOS for your device can help isolate potential software issues. Kindly secure a backup and update.
How to back up your iPhone, iPad, and iPod touch
Update your iPhone, iPad, or iPod touch
If your device is already up to date, we recommend that you check for app updates. You can use the article below as a reference.
Update apps or use automatic downloads
Also, we recommend that you try the steps in the "Learn more" section in the article below.
About the Apple USB-C Digital AV Multiport Adapter
We would also like to set your expectations. If you are able to mirror your iPad's screen except when using apps with streaming services, it is likely that the issue is app-related or an expected behavior for these apps.
If you are looking for other ways to stream video or mirror your iPad's screen, the article below may help.
Use AirPlay to stream video or mirror your device’s screen
Take care!