Hi have two budgies taro and gumi, gumi is relatively new like 3 months maybe? They get along great, preening each other, regurgitating for each other and just chilling together. Problem is gumi always chases taro around sometimes flies at taro. Anything taro does gumi suddenly wants to do and tries to sometimes push taro away, they're not properly fighting like attacking each other but I just don't understand what's going on.
Here are my thoughts.
Do you know their gender? I wasn't sure if she's new as of 3 months or if she's 3 months old. If they are a little older, I know sometimes budgies do chase each other around as a form of play. But it can also be one budgie feeling a bit frisky. The reason I suspect more of a "romantic" thing, is that you said they regurgitate for each other.
As far as play goes, In my experience raising budgies, there is a lot of switch between one being more dominant with another by tapping their beak, stepping on their tail or chasing them around. From what I've noted, this is almost always just a form of play. But it's not always reciprocated by the budgie being pursued. They might start to get annoyed if they just want to chill and snap at the budgie that's bugging them. This usually results in the other one backing off, but not always lol.
Here's a good example of what I mean. These are my budgies and my conure Simone. Franklin was feeling playful and no one else was:
As long as they aren't actually hurting each other, it shouldn't be a problem. If it's more of a romantic situation, you might give Taro a little space by distracting Gumi or separating them when she starts to bother.