firstly ensure that the same 2 wires connected at the xnte are continuous throughout your home. use the blue pair for continuity.
if you have no dial tone at the xnte then you need to chase your provider, the issue will be that the line may test ok but its not at the right premises.
where abouts are you?
lastly, there should only be extension sockets in the house s the xnte carries the capacitor for which the test systems look for.
these comments are my own and in no way represent any company that i may or may not be linked too.