I have two separate data columns. Col B has only last name, and Col D has
last name, comma, first name.

I'd like ALERTs in the F column if everything to the left of the comma in
D2 Does Not Match exactly with B2, and dragged down. If it matches, then
nothing.
Something like this.
B D F
Montana Montana, Joe ""
Young Brady, Tom ALERT
Unitas Unitas, John ""
Bradshaw Young, Steve ALERT

Thanks,

Steve