[Ashish Kumar (Ashfame)]

Which version of bbPress are you using?

If you have phpMyAdmin access, then open the usermeta table (should be bb_capabilities if you are not using shared user tables and should be wp_capabilities if you are using shared tables) and change the value of bb_capabilities to a:1:{s:9:"keymaster";b:1;} for your user.

Hope that helps.

P.S. – Change the default table prefixes as your case may be.