Traffic from "internal" to FortiSwich VLANs is dropped, for unknown reason.(reverse ok)

Hi,

Please share the output of this command and try to initiate a traffic:

#diagnose debug flow filter saddr x.x.x.x
#diagnose debug flow filter daddr x.x.x.x
#diagnose debug flow show function-name enable
#diagnose debug console timestamp enable
#diagnose debug flow trace start 1000
#diagnose debug enable

Once you capture the output, please execute the below command to stop debug:
#di de di

BR,

Manosh