In many situations port forwarding doesn't work. I have found this in my personal experiences. Actual cause of the failure remains unknown most of the times. Also many ISPs notoriously close various ports randomly. Port triggering may serve purposes in some cases. This is not exactly an answer to your problem, I know. Take this as a general purpose comment on the port forwarding problem. I am not an expert in the field. Please consider my comments very general purpose.

In many situations port forwarding doesn't work. I have found this from personal experiences. Actual cause of the failure remains unknown most of the times. Also many ISPs notoriously close various ports randomly. Port triggering may serve purposes in some cases. This is not exactly an answer to your problem, I know. Take this as a general purpose comment on the port forwarding problem. I am not an expert in the field. Please consider my comments very general purpose.