Unanswered Giant Reign Crank Arms

[Samphaa7]

Hi guys,

I hope this is the correct place to post.

My Reign E+ has developed creaking cranks, they've both got a small amount of play in them. Plan was to take them off, apply some new grease and torque the bolts back up to see if it solves the issue, however, when trying to undo the crank bolts, they slacken off initially and then go tight, it's like they tighten up both ways, I'm unsure if they're meant to tighten up against something to push them off, but I'm hesitant to just keep forcing it incase I strip a thread or have something go wrong.

Bike is fairly new, covered approx 200 miles.

Thanks