There is another possibility
In York there used to be an issue near the Vue cinema where there was a branch of 'Frankie and Benny's' that used to have those 'Your Table is Ready' plastic flashing pagers.
The problem with the pagers was that the frequency they used to transmit on was also 433Mhz - which meant that most people trying to park their cars outside the site used to suffer with the same issue - they couldn't lock their cars if they parked too close to the restaurant.
My car (a hateful Peugeot 407SW) used to suffer with this - I really couldn't park it anywhere near the restaurant as I couldn't lock/unlock it. The first few times I thought it was my car being duff when parking for the cinema, and once I got totally locked out of my car. I worked out that if I moved it further away down the other end of the car park it would lock/unlock fine.
Eventually they changed the pagers in the restaurant and the issue stopped happening.