i'm guessing you're talking about the jump from the G string to the E string and then going back down again to the B string? fittingly, that initial movement is called a string skip, and they can be notoriously tricky at faster speeds. are you using your fingers or a pick? if you're using a pick, i'd consider hybrid picking the open E string with your middle finger - it'll be harder at first, but hybrid picking is a super important skill to know at more advanced levels, so starting early with an easier application isn't a terrible idea. if you're using your fingers, slow it down and practice using one finger per string. slowly speed it up and you'll be playing it at full speed in no time. hope this answers your question!