The subscription right provided as part of the porting request is invalid
The subscription right provided as part of the porting request was not accepted by NTT. Certain NTT plans only allow one subscription right, see the solution section for which one you should use.
Some NTT plans only allowed to request specific subscription rights.
If your current NTT plan is the "Light Plan", then only the Termination subscription right will be accepted by NTT.
Otherwise you should request the subscription right "Suspension".