i have received the n172 (or the letter in the post) but not replied yet. I have a few weeks to reply . My vision is fine, but i couldnt pull into the correct (green) lane in time because of other cars

I recently was on the M1 driving ,and got flashed on a camera. Not for speeding but for staying in a lane which was closing (red light). I didn’t get into the correct lane quick enough, as there was cars in front of me etc. im just seeing if there is any point or option of appealing it. Does anyone know or have experience of this ? Or etc any Facebook groups which could help. Thanks very much for your time