The term "gotten in one hair" is a somewhat obscure phrase, but it essentially means getting overly fixated on a particular issue or point of contention. There are a few synonyms that can be useful in conveying a similar idea, such as being stuck on a particular topic or point, becoming entangled in a specific issue, or getting bogged down in one aspect of a broader conversation or debate. Other options might include getting hung up on a particular issue, becoming obsessed with one point, or becoming overly focused on a single element of a larger situation or problem. Ultimately, there are many ways to convey the idea of becoming fixated on a single aspect or issue, but the key is to remain aware of the broader context and to keep a sense of perspective.