Most likely an issue with your router not accepting loopback connections.
I initially had this issue with my PFsense setup and had to enable 1:1 NAT Reflection to get this to work.
Might want to take a look here: https://help.ubnt.com/hc/en-us/articles/204952134-EdgeRouter-NAT-Hairpin-Nat-Inside-to-Inside-Loopback-Reflection-