Enhanced DBS Check taking too long

I was offered a job, had to do an enhanced DBS check. It has been 5 weeks and my DBS check is still 'submitted, awaiting countersigning'. How much longer is this going to take? Is there anything I can do other than wait?

Context:
-This is my first time working in London, my last DBS check was 7 years ago in Bristol
-I had a DBS check done as a volunteer by the same company, but I guess its a different DBS now that I'm going to be a permanent employee.
-I change addresses a lot in September-October because I was in between houses.