In humans, lop-eared (B) dominates the gene for normally closed ears (b). What are the genotypes of parents

In humans, lop-eared (B) dominates the gene for normally closed ears (b). What are the genotypes of parents if among their children there were 50% lop-eared and 50% with normally pressed ears?

Children with normally pressed ears are homozygous for this trait, their genotype is bb, and lop-eared ones are heterozygous – Bb, their ratio is 1: 1. Knowing the genotypes of children, it is possible to determine from which types of gametes they are formed.
F1: Bb x bb
gametes: B b b
So the genotypes of the parents are P: Bb x bb