Hey i want to ask, if the person has 2 alleles , 1 positive with sickle cells another is a normal function allele.

So is the sickle cell allele still working and you make false proteins but with the another allele still works normally then you still can be alive because your blood now consist both false hemoglobins and normal hemoglobins ( and the normal hemoglobins is in sufficient amount for you to be alive ? ).

I thought at first if an allele is reccessive and another one dominant then the reccessive allele will be locked , only the dominant will be working or switch ON. So whats wrong can you please explain..