LED number plate lights

[GuidoB6]

I recently bought some LED number plate lights, I specifically bought CAN BUS free LEDs because i thought normal LEDs wouldnt work.
I went to put these new ones in, i put them both in, straight forward to replace, turned the lights on, it worked for a few mins and then stopped working, I took them out several times to move them a bit and switch positions, and still the same. They work for a but then just stop working. its not like one of them stops working, its both at the same time?
This was confusing me, anyone had any experience with these?

Cheers