Tacx Neo Smart Bike - Left Hand Crank Arm Issue

Hello,

I think i can see a common problem with the Left Hand Crank Arm on the Tacx Neo Smart Bikes. I am having the same issue. Hopefully you can see the picture of my Crank Arm.

You can see the gap and as im riding the Gap increases and decreases, but the gap is getting progressively worse. Is it a case of tightening the Allan Bolt, once i have pushed the Arm back as close to the bike as possible? Or is there something else i need to do?

Your help would be greatly appreciated

Andy