Would anyone know, please, how I can replace the audio that was cut-out when I inserted a photo into my video stream?

I managed to split and insert a photo into the video stream. However, when I cut-out the frame to insert the photo it seems to have also deleted the audio that was with it! So, now my video has talking audio then silence while the photo displays, then back to talking audio for the rest of the original video content.

(I wonder whether there is a way when doing it to duplicate the original so it isn't totally deleted?)

(This inserting photo into video stuff seems to be a major problem from what I can see in the forums. And Microsoft hasn't addressed it - That's why I'm looking for software that CAN manage it).