The credit union shall have a lien on the share accounts and accumulated dividends of a member for any sum owed the credit union by said member and for any loan endorsed by the member. The credit union shall also have a right of immediate setoff with respect to every deposit account. The credit union may also refuse to allow withdrawals from any share or deposit account. The credit union may waive its rights to a lien, to immediate setoff, to restrict withdrawals, or to any combination of such rights with respect to any share or deposit account or groups of such accounts.