Closed HP wash unavailable?

Hello.. Sh4dysh4d here

My question is in short, why cant i wash mp into hp if i have more than minimum mp and also gather every lvl from 70 onwards,like 18mp extra per lvl.

ive got with int gear 186 total int (will be upping this next lvl with ap to 190 total)

but still when i wanna use an APR the option to mp down is grey..
ive start using int gear and upping my int from lvl ~52 and doing this every lvl untill now..
is there some kind of bugg, or do i do something wrong?

i hope anyone can give me the right answer,

thanks in advance!