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How to re-wire this switch with three red wires?

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I have a bedroom light switch that was removed and I’m trying to wire it although there are three red wires and I’m not sure which goes where

There is also another light switch in the bedroom on the opposite side of the wall if that has any relevance.

I have attached a photo, any suggestions would be appreciated before I call a sparky for this small but important job.
Just to add when the light switch was originally removed it had two of the red wires in one of the light switch terminals and one red wire seemed to be hanging loose. The blacks were in a separate connector.
 

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Put any two reds in com and the other red in L1, then rotate the three until it works as it should.

Power off when rotating obviously.
 
I have a bedroom light switch that was removed and I’m trying to wire it although there are three red wires and I’m not sure which goes where
Why was it removed?
There is also another light switch in the bedroom on the opposite side of the wall if that has any relevance.
Does/did this other switch operate the same light?
If so, a photo of the wiring existing at that switch would be of assistance.
Just to add when the light switch was originally removed it had two of the red wires in one of the light switch terminals and one red wire seemed to be hanging loose.
Was it not connected?
Did the light work at that time?
The blacks were in a separate connector.
Where they still are.

You need a new box - one of the screw holes has 'gone'.
OR,
obtain an appropriately sized nut
and
fix it in position, using Epoxy Resin Putty.

(https://www.amazon.co.uk/s?k=epoxy+...esin+putty,aps,334&ref=nb_sb_ss_ts-doa-p_1_17 )
 
It looks like there are three T&E cables. Two have the black wires connected together, the third cut off.

It seems reasonable to me that the former two cables are feed in and feed out (L and N), while the third red is the switched live. That means the bottom two reds into common, the top left one into L1 and see if everything works.
 
Put any two reds in com and the other red in L1, then rotate the three until it works as it should.

Power off when rotating obviously.
When rotating..

One option allowed the switch (switch for bedroom 1) to work correctly however the light switch on the opposite wall (switch for bedroom 2) then only worked when switch 1 was on.

I then rotated and switch 1 was on constantly whilst switch 2 only worked when switch 1 was on.

The final option worked!

Typical had to be the last option! Thanks for your help. I owe you a beer if you’re ever in West Yorkshire area.
 

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