I want to know whether this sentence is grammarly correct or not:
As a person who is 50 years old and who has been working in this field for 27 years, he is an expert for sure.
I was thinking should it be:
As a person who is 50 years old and has been working in this field for 27 years, he is an expert for sure.
The sentence I want to write has the same structure as the first sentence. Is it correct to use two "who"s like that?
I know I can place the "50 years old" in front of the "person", but I am interested in knowing whether this kind of structure works.