Block specific User group to update BP info Except one B1

Hello

I want to block a specific group of user POS , that i created with several autorisation , to update any info from All Business Partner except the main by default BP from A/R Invoice + Payment Tab which is "CL0000" in our compagny . (they need to update contact info)

I know we can do it with SP_Transactionnotification in B1 et SQL but i do know how to use it.

thanks.