Not quite sure how a maxle works but I have had the same issue with a qr.
Have a look at the spacer that goes on the end of the axle parts 20 or 22 etc and look at the O ring inside. The metal that is between the O ring and inner surface may have cracked. So when it is nipped up the end part clamps against the outer bearing race locking everything up. It may look ok when you take it off as the o ring will hold the broken bit out in place.
I have had 2 do this on a qr set up. Drove me crazy trying to find it.
Seems like a major design flaw as the whole clamping force (on a qr at least) is taken on 2mm of aluminium.
I sent a detailed set of pics to Hope explaining the issue but no comment.
I now keep a spare in stock and when the next goes will send it back to Hope.