[Grammar] Time clauses - Reported Speech

[barnej0096]

I have a question about reported speech. There are 2 sentences:
She said, "When I was swimming, I got a cramp." ---> She said that when she was swimming, she got a cramp.
"What did you miss most when you were in prison?" Mary asked Jim. ---> Mary asked Jim what he had missed most when he was in prison.
I don't understand why there is 'had missed' in the second sentence. It's a time clause in past simple so it should not change into past perfect.

 

[bhaisahab]

I have a question about reported speech. There are 2 sentences:
She said, "When I was swimming, I got a cramp." ---> She said that when she was swimming, she got a cramp.
"What did you miss most when you were in prison?" Mary asked Jim. ---> Mary asked Jim what he had missed most when he was in prison.
I don't understand why there is 'had missed' in the second sentence. It's a time clause in past simple so it should not change into past perfect.

"What happened when you were swimming?" Jim asked Mary. Jim asked Mary what had happened while she was swimming
If you are going to compare sentences, compare like for like.