Poor customer service

It was my favorite restaurant, quality is very good. But:

Now is 3 times I went there and I see very bad behaviors from the their team, specially from the person stay at the gate. They write my name for reservations I waited 45 minutes then they said we do not have space yet. We were 3 persons, they have it but because I said I am not happy then they give it to 2 persons. that came after us (the table that for 3 person) They are very for customer services.