Rangefinder button also starts the lock for SAMs for some reason

I have Fire from special guns and Weapon lock on my mouse, both start the locking process for SAMs but for some reason my Rangefinder button R also starts that process.
Why?

Are you sure you don’t have any radar keys bound to the R key, even as a secondary button?

Yes, I am. It even happens if I unbind all the radar and weapon lock buttons

Strange, maybe try to bind to side keys if u have it, or see if the binds of anything has R as well.

Nothing for locking SAMs is bound to R even in the other controls for Planes or Helis R is not bound to anything that has to do with weapons