Audio track not showing properly times where I speak

I am just starting editing and it all seemed easy after this great course, but I have a problem.

I recorded footage and it all looks good when I play it however on the audio track I was counting on the audio waves to signal where I was talking and where I was not.

However somehow the waves showing on the audio track don't seem to match my talking at all. There are plenty of times where things I say on the video aren't being shown on the audio track visually and hence it makes it super difficult to edit and cut parts where I don't actually talk.

Can someone help?