How to stop RTN charges?

I'm curious to know, what exactly are RTN charges and why do they occur? Are they fees associated with cryptocurrency transactions or are they related to something else entirely? And if they are indeed fees related to cryptocurrency, is there a way to prevent them from being incurred? Perhaps there are certain steps or practices that one can adopt to avoid RTN charges altogether. Additionally, if RTN charges are inevitable, are there any strategies for minimizing their impact on one's overall financial standing? I'd appreciate any insights or advice you can provide on this matter.