HANDBAGGAGE CONTROLS
If as your title suggests you are indeed a dispatcher, then surely you are in overall control of the flight and indeed the boarding agents ; therefore you should ensure that the hand luggage let through the gate adheres' to that particlular airlines regulations
Boarding agents by nature of their job may miss the odd bag; equally they may not be aware of the restrictions applicable to the a-c they re boarding - maybe a 'briefing' before boarding would help
Part of the problem I have found is on turboprop a-c with a light load - ground crew seem to think it ok to allow trolley bags etc. onto a-c saying 'oh, its not full today you should be ok'
This is fine until next time the same pax says 'but last time it was' ok', neglecting to mention that the a-c was ½ full - this only inflames the situation on board