New granite - is this acceptable

Hi,

I just had a new granite counter top installed in a new bathroom. We don't have much experience with this kind of thing and noticed this on the back splash (see image). The line you can observe is not stone, but something softer (some kind of epoxy).

Is this kind of thing acceptable? I know natural stone isn't perfect, but in my opinion this looks bad.

How can they fix something like this? Is it possible to remove the backsplash or will they have to replace the whole counter top?

I haven't been able to connect with the stone person yet, but should I expect push back?

Thanks,
PB3