People want to get a single parrot because if they get two then the parrot won’t like them as much.
But then they don’t want the parrot to view them as a mate.
What did you expect? You got a pet in which most species mate for life. Their lives revolve around their mate, preening their mate, feeding their mate, having sex with their mate, raising babies with their mate, driving away competitors from their mate, and yes, spending their entire life with their mate.
You prime them for this situation by you or a housemate being the only ones available, and then freak out when they want to do this to you. It’s natural. It’s not bad. Your parrot isn’t misbehaving, it isn’t a bad bird just because you are keeping a wild animal in a captive situation where it just wants to do what every feather on its body is telling it to do. Stop treating it like such, stop punishing them for displaying mating behaviors.
Do what you signed up for by getting a single bird or work to get your bird a feathered mate. That doesn’t mean buying the first bird at the pet store you see and throwing them in a cage together and wondering why they don’t like each other. That means becoming a match maker and setting up play dates, or even consider rehoming your bird to someone who can.
Stop buying parrots and expecting these wild animals to be pets. They’re not. We’re on the way to domesticating birds like budgies, cockatiels, love birds, Indian ring necks…but we’re still so far from being able to keep them happy and healthily easily like we are with chickens and pigeons who thrive with us. Hell, starlings make better pets than parrots since at least they often choose to be with us.
And please, when you’re researching any animal don’t do a quick google search. Talk to as many people as possible, both new owners and experienced owners.