How to un block 1-900 numbers?

Question

im trying to become a runescape member by phone it says to dial 1900-457-3555 i dial it and it says that srry your cal can not be compleated as dialled so people are telling me that its becasue i have 1-900 numbers blocked howdo i unblock them and is thier any drawbacks to unblocking these numbers>

Answer 1

only the owner of the phone line has the authority to have the phone company unlock the 900 number