Problems w recording

I’m using GarageBand on my iphone7 and experiencing consistent problems and hope someone can help me.

Example: I recorded a keyboard part and I made a mistake so I deleted the track and tried to record again and at the spot where I made the mistake there is no note. It picks up after that. Even more troubling is if I go on another track w same keyboard to fix that one note and play the notes, when I listen back it’s not there.

Now the even even weirder part, if I’m recording another part, say horns in that same section and I begin at that exact time where my missing notes started it and I play a new part it’s missing that first note.

This is is driving me crazy. Cannot figure out how to fix this and it’s happening w me every time I record s track so perhaps there is something I’m doing wrong that I can avoid so this problem does not continue to rears it’s head.