Problems with adding new filter in the "Flow" App

Hello Experts,
For restricting file access on our nextcloud-Plattform we have configured a flow of 12 filters and it is working as it should (See screenshot attached).

Problem now is with adding a new filter. Every time I try I get an error message that the configuration is invalid. We configure this settings in the Year 2019 as the app was formerly called “File Access Controll”. Has maybe something changed regarding the configuration of filters? or could it be a bug?

I would be very thankful for some tipps :).

Best regards