Grant a level

Q u o t e:
i cant not grant my linked friend levels im 17 atm and hes 15 and its greyed out i can summon him though any one know why?

If you are referring to the priest on this account that is now level 19 - and online, I show no grantable levels left on that character at this time.

You are the recruiter, he is the recruit. HE has 6 grantable levels on that warlock. The recruited account grants the recruiter account levels, not the other way around.

The Recruit a Friend FAQ is here....

http://us.blizzard.com/support/article.xml?locale=en_US&articleId=20588

From page 2, there are restrictions.

Are there are any restrictions on granting levels?

Yes:

1. Levels may only be granted to characters on a veteran account by characters on a linked recruit account
2. Levels may only be granted to characters of the same faction and on the same realm
3. Levels may not be granted to characters over level 59
4. Levels may not be granted to characters of equal or higher level
5. Levels may not be granted once a 90-day account link breaks
6. Levels may not be granted to veteran characters with XP gains disabled.