calling AccountManager#getAuthTokenByFeatures from multiple WorkerThreads at the same time

Question

Background I am using AccountManager with a custom account type. In the beginning the App starts the user LogInActivity and a token recieved by the server is stored within the account. The tokens are used by some Worker organized by WorkManager to sync data in the background. Each worker is requesting the token with AccountManager#getAuthTokenByFeatures(). When the user is changing the password on the website connected with the server, the token is expired and the AccountManager is starting (due to password change) the related LogInActivtiy.

Issue If during the user input of the new login data other (parallel running) Worker are requesting an AuthToken, the LogInActivity is started multiple times.

Solution Approach

1. Setting android:launchmode="singleInstance"of LogInActivity -> only one Activity is started, but second, third, ... calling Worker results in deadlock due to no return of AccountManagerFuture<Bundle>.

2. Creating Workaround: AccountAthenticator checks if an Instance of LogInActivity is allready running in Foreground and starts all further Activities invisible in the background. If LogIn was successfull all in the background running LogInActivities recieving necessary Information via LocalBroadcastManager -> LocalBroadcastManager is deprecated, power consuming and unnecessary overhead

Is the use of AccountManager in combination with WorkManager correct in this case? Might there any configuration issue with AccountManager causing this behavior? Any other solution approaches?

Help is really appreciated. Thank you!