This article explains why ProBackup may ask you to reconnect your app and what to do when it happens.
Why re-authentication is needed
When you connect an app to ProBackup, an authorisation token is created that allows us to access and back up your data. In some cases, this token can become invalid, for example:
The token has expired.
You changed your password in the connected app.
Your app's admin revoked third-party access.
When this happens, ProBackup can no longer back up your data until the connection is renewed.
What to do
ProBackup will send you a warning email when a connection needs to be renewed. To reconnect:
Go to Settings > Apps.
Click "Reconnect" next to the affected app.
Follow the prompts to authorise ProBackup again.