I have recently installed a Dahua smart 1U DVR with Dahua cameras at my home. 
Within my home Network I can connect via my mobile and see my camera's live streaming. For this connection I used the IP/Domain category in the gDMSS Plus app. 
  
However, for remote viewing away from home this setup wont work. I tried using the P2P category in the gDMSS Plus app to work and it "Fails to connect. I scan the QR number and follow the steps as its rather simple. I tired trouble shooting without success. 
  
Please assist. 
  
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