When you get blocked what error or what else happens?
What do you mean by getting stuck? Where you get stuck? When? Dgraph-js throws something?
Not really. This can be anything. It can be that you tried to mutate the same predicate with @upsert directive. It can be that your mutation had some conflict. And so on. What you can do is restart the servers and wait for the abort to be completed. And this log will go away.
You can set the flag --abort_older_than to less than 5m.
But you need to find out where is the problem, and it is related to the usage itself.