what to get

First of all, could you work on typing correctly? It makes everything much less confusing.
To answer your question, you need to either just work on keeping the string in the center. Sometimes this isn’t possible in which case you either need to made your gap bigger (if you have an adjustable gap, which the Dark Magic has) or if you don’t have an adjustable gap you need some shims or spacers.

Could you tell us what skill level you are at? Like what is your best trick?

If you don’t what it to hit the side then either pratice or you can buy a konkave bearing.