When I watched the video for the first time, it was not clear to me. It was [[only clear]] the third time.
I couldn't follow the video the first time so I had to watch it a couple of times. <- Good sentence
I could follow the video [[after]] watching it for the third time.
His contact [[left]] the conversation and [[talked to]] someone else. <- Grammatically correct but use of the present tense is somewhat rare, literarily.