Reverse and brake lights not working after camera install

[Tetleycat]

Hi - just been fitting a reversing camera (Autovox V5 Pro) to my 2018 T6. While doing this I've removed part of the roof paneling and disconnected one of the rear interior lights (not sure if this is relevant). When I've tried to find the reverse cable to connect the reversing camera, I've found that neither the reverse light or the brake lights are working. The rear lights and indicators are are ok. As part of the fitting, I removed the front passenger seats (now refitted and reconnected) and piggybacked the unit to both a switched live and a permanent live fuse (as per the instructions). Again not sure how much of this is relevant.
Any idea what is causing the reverse and brake lights not to work? The battery also seems to be draining.

 

[Niknak]

Connection for the rear lights is practically under the front passanger seat think it’s a green plug from memory, check there for water ingress and can also check here for feeds so you can pinpoint if fault is with front area of cab or load area

 

[Tetleycat]

Cheers - I'll give that a go. Hopefully just a loose connection when I reconnected after refitting the front seat.

 

[p6raf]

Connection for the rear lights is practically under the front passanger seat think it’s a green plug from memory, check there for water ingress and can also check here for feeds so you can pinpoint if fault is with front area of cab or load area

Sorry to bomb your old post. Out of interest that green plug you mentioned... is there a reverse wire there?