Steps to regenerate -
1) Navigate to manufacturing -> Routing
2) Press New Routing button.
3) Try to create a routing without entering Routing Name. It will not allowed to create the record as routing name is mandatory field.
4) Create routing by adding proper details.
5) Now, select newly create routing from manufacturing -> Routing
6) Try to update selected routing with empty Routing Name.
Actual : Routing can be update with empty Routing Name.
Expected : Routing should not allow to update with empty Routing Name.