I appreciate "your time helping me" or "the time you spend helping me"

Hello. I wrote these two sentences but I'm not sure about which one is correct and more natural. I used a spell checker and it says the word order is correct but I'm not sure about the way they are composed.

A. I appreciate your time helping me and I hope I can return the favor.

B. I appreciate the time you spend helping me and I hope I can return the favor.