Form 3+ Mixer detaches and jams beneath build platform

Hello lovely folk of the Forum. Now - I may be just plain unlucky here, but am trying to stay positive!
Last week my Form 2 started to fail on every print - Formlabs tell m Amy laser is too weak and I needed to replace the machine with a Form 3+. I did so, painful as it was on my pocket!.

new machine arrived today. Went through the setup as instructed. Fitted the resin tank and Mixer. New litre of Clear V4 to start the process off. Took and absolute age to fill compared to the Form 2!

the wiper (sorry mixer) became detached as it was wiping across the dry tank and I got an error saying ’ Mixer check failure’. Took the tank out, checked all was free and that the magnets were in position etc. Looked fine. Reinstalled and tried again. Same thing. Thought the lack of lubrication (being a dry tank) may be to blame, so I tipped resin in and that seemed to solve the issue. Machine heated up and started to print. Layer 1 fine… Layer 2, the mixer popped off its home position and sat about 10mm under the left side of the build platform. I stupidly assumed/hoped that it would reset itself before the platform came down for layer 2. Alas not! A clunking sound was heard. To make matters worst, the machine didn’t even flag this motor jam as an error! My old Form 2 used to interrupt prints all the time even when there wasn’t an obstruction.

Hated that wiper on the form 2, and cannot believe they’ve come up with something worst on the 3+!

My question is, do I simply have a dodgy tank, could the machine be at fault or something else… As far as I can tell, I’ve followed the setup to the letter. At an absolute loss. Any help would as always be massively appreciated. Best regards, Scott.

An update***

I realised that the little plastic ‘tabs’ sticking out of the mixer/wiper kind of help the part stay fixed in place during the print. I ‘bent’ them slightly to add more friction to the sides of the resin tank. Trying a print again. this time all is good. The mixer does its thing early on for the first 20 or so layers, then stays in the home position for the rest of the print. I’m 75% through thus far and all looks good. Will keep you posted, but it looks like a simple mechanical fix. Fingers crossed.