Rear Bumper Light Unit

Well it was broken and need replacing, off we went ordering one which arrived on Friday..

Look a very easy job, but when fitting the need one in position, the retaining clip A kept popping out...

Anyway what am I doing wrong. this part doesnt seem to clip in, theres no click noise to confirm its fitted and secure in place... half expecting to be driving down the road and either lose it or find it hangging down from the bumper

Oh well with a wack from my hand it seemed sercure, but have cracked the new one ...not a good day at all, maybe to forceful ...lol

had the same prob on my disco 2 but i just bent the little spring clip until it snapped into place .

When it falls off, let me know - I've got a spare one.