Match frame from the in point of the audio (shift-f).
Select the gap in the timeline if it’s a gap clip, or mark the range if there’s no gap clip.
If there’s a gap clip, hit shift-2 to switch to video only mode and hit option-r to replace from start. This should replace the gap clip with the match framed video from the audio in your timeline.
If there’s no gap clip and you marked a range, hit “q” to add the video as a connected clip from the matched framed audio.
Afterwords, hit shift-1 to make sure you switch back to audio and video editing mode.
If this makes no sense to you, send a screengrab of the area of your timeline.