Certain Names that can't be taken (for no apparent reason)?
Some names which aren't offensive AT ALL are colored brown. Minecraft won't let you change to them either.
For example, "SirJava"
w t f
Same, my og name of my alt (TheDragonMC) is locked aswell, and idek why.
This could be because minecraft runs on java, and they don't want a chance of a trouble-causing user having a name affiliated with it. That's my two cents.
I've seen the same thing with the ign "Prudent". Wont let me change to that ign
If they're like that, Mojang is blocking it for one reason or another.
A lot of them may be the profanity filter being overly-sensitive but some may also be specific reasons where support blocked that name temporarily or permanently. Their API doesn't show the reason names are blocked unfortunately.
I would not ask them about it though, if it was a mistake it will be unlocked eventually and I've never heard of them unlocking a name for someone who asked, so don't bother them with it.