Hi Philippe, thanks for contacting me to let me know about this. I'm sorry you have experienced this issue trying to access a downloaded beat link from your teacher.

In most cases, I've solved this issue by first force-closing the app on your device and then again opening the link. Force-closing the app involves bringing up the app switcher on your iPhone or iPad and swiping the app off the top of the screen. 

Force-close on iPhone: https://support.apple.com/en-us/109359

Force-close on iPad: https://support.apple.com/guide/ipad/quit-and-reopen-an-app-ipad79518d15/ipados

If this doesn't work for you, then the best way for me to support you for an issue like this is one-on-one through email. Please send me an email from Beat Note by tapping on the Settings tab and then Emailing Derek, and we'll get this resolved for you as quickly as possible. 👍🏻

Thanks for supporting Beat Note!

Best,

Derek