ParseRequestException: i/o failure occuring with app in background

Question

I see this crash in firebase's crashlytics, with 99% of cases while app is in background:

Non-fatal Exception: com.parse.ParseRequest$ParseRequestException: i/o failure
       at com.parse.ParseRequest.newTemporaryException(ParseRequest.java:288)
       at com.parse.ParseRequest$2.then(ParseRequest.java:142)

Caused by java.net.UnknownHostException: Unable to resolve host "ourparseserver.cloud": No address associated with hostname
       at java.net.Inet6AddressImpl.lookupHostByName(Inet6AddressImpl.java:156)
       at 
Caused by android.system.GaiException: android_getaddrinfo failed: EAI_NODATA (No address associated with hostname)

The app uses a subclass of AbstractThreadedSyncAdapter to handle syncing between Parse server and local database.

Does anyone know how to fix this issue ? Could it be related to AbstractThreadedSyncAdapter trying to do some syncing when app is in background ?

Note: I already checked similar questions and answers, such as missing permissions, checking internet access... but none of them help. This issue is different because it involves Parse server and AbstractThreadedSyncAdapter.