Hey @devApps
This is power pages forum. To get answers related to Power Apps quickly. You may need to find the right one.
However, for your issue. I am adding some ground rules when you work on canvas app
1. Always refresh the browser and re-authenticate before you start your development.
2. If you have too many sessions running, there is a possible network glitch.
Best practise:
1. Enable git version control in power apps. Official link here
2. Raise a support ticket with the Microsoft helpdesk: Official link here
NB: you may need to provide your app session id to resolve this issue quickly. They will guide you on how to get this.
Hope it helps.
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