You can try ear drops from the chemist, but they don't work for everyone - including me. I made an appointment with my GP, who eventually agreed, reluctantly, that the nurse would do it if a week of ear drops didn't work. It didn't, and it took two visits to the nurse before it was sorted.
You have to be persistent with your GP and not let them fob you off. It is a genuine problem that I don't think they take seriously enough.
NB if you have dry skin this can cause blockages as it makes a plug with the wax. A few drops of oil every week can act as a preventive but is not a cure.