Im arab but people refuse to accept my race!?

My parents are both arab ( dad is Algerian mum is Lebanese) & although i was born it england my ethnicity is arab! anytime i try to say anything about my culture people will say 'Yo were born in england therefore you're english stop saying your arab' I FIND THIS SO IGNORANT AND ITS REALLY STARTING TO ANNOY ME! how should i handle this?!