Ubiquiti UF-RJ45-10G do not lock in place!

I posted this issue on the Ubiquiti forum, but there has been no response. Pictures show that the likely reason is that the mechanical tolerances are too tight on the triangle key on the module so that it doesn’t insert into the triangle socket on the switch.

Does anyone have experience with SFP+ modules not locking in place?

I have never encountered that but I don’t have any Ubiquiti 10G modules as I am using the ones from fs.com

Me neither. I have used:
Intel 10GB SFP
Ubiquiti 1GB, 10GB & RJ45
10gtek SFP and DAC
In the 16XG and X520-DA2.
Never had one not lock in place, sorry.

I’ve encountered times when the module had to be wiggled and encouraged a little in order for the lock to engage. Most recently was a 10Gtek module into a Ruckus switch. While it is a little disheartening that you’re experiencing that with a “first-party” module, things happen.