in odoo 13 in administrator user ... that happened  when i activated handle by odoo and odoo receive all time off action in inbox and discuss of system

and i deleted some time off record that created by test user ... and didn't open that notification or massage 

tel this time every time i open Discuss ...show me old massage and same notification for new user invite  and it couldn't delete 

and when i press on view time off in discuss screen all massage disapper but when refresh or open new tab show me old massage and same notification for new user invite  and it couldn't delete 

can you tell me how to solve this issue and delete that fake screen and massages