Oh no! Please don't give up! Do you have them caged together? If so, perhaps separating them for awhile would help, and rebonding with them... work in the cage again, building that trust, and perch train them again, in the cage only. Sure, it may be frustrating, but keep in mind, (and I say this with respect) that they are not robots- they are living beings with a brain that doesn't think like we do. Perhaps something startled them and broke that trust. I would certainly not let them back out until they are 're-trained', that would just reinforce their new bad behavior. Or maybe just one at a time? But please don't give up on them. Every budgie is different...if they have been caged together, they have bonded to each other instead of you.