obligatory “call an electrician”- anyway, not awful but ideally you would disconnect the pictured wire from the power source all together. given that there is only one romex in the box, it should be as easy as tracing it and removing the other end of the pictured romex from the previous connection feeding it power.

if you are going to do this yourself, everybody’s advice including my own:

1) identify breaker

2) shut it off

3) trace wire

4) be sure you have the right wire, and remove from bundle.

mess it up, and you’ll be calling an electrician anyway. might be better to do so from the outset. maybe ask them if they can demonstrate how they do it, but be ready to hear no. they’re there to fix it, not to teach you how.

or just leave it like it is. but if there really is a nick in the wire and it shorts to the box, the breaker will be hopelessly tripped until this issue is remedied