Scoring help?

Recently my Dad and I were playing a game and I had a run of 9,10,J,Q, all diamonds. The starter card was a 6 of clubs. The question is does that run score as 8 points being a run of 4 and all the same suit, or only 4? I thought it was worth, my Dad thought only 4 (because you can't score the same cards twice). Which is correct?

I've always played that you

I've always played that you get the 4 points for the flush as well as 4 points for the straight for a total of 8 points but I don't know which is officially correct.

Eight points. You can count

Eight points.

You can count things twice as long as it is for different reasons.

Score 10 not 8

Four for the flush, four for the run and one fifteen.

Score 10

Your hand is worth 10 points. The run of four, four for the flush and one fifteen.