A4 2.4 Convertible 10 amp Brake fuse

I was checking the fuses on my 2002 convertible prior to a long journey next week. I pulled out the red 10 amp brake light fuse to check it (position 14 in driver's side fusebox). I tried to put it back in and it will not engage properly now. Have tried all variations. Now I have a red brake light warning and an "ABS - bring to Engineer" message. I have tried another working 10 amp fuse in the same slot but again the fuse does not engage fully, it flops about! I was very careful removing the fuse the first time, using the white plastic pincers that are provided so I haven't damaged the receptor. Any advice? Many thanks in advance. Helen