Lead in Conduit repair

Attempting to get NBN connected at a new-ish build in Adelaide, around 3–4 years old. We’re currently using 5G and were hoping to move to a fixed-line NBN connection.

The NBN technician attended but couldn’t complete the installation. The report says:

“Summary:
The nbn technician identified that the lead-in conduit was damaged, approximately 1 meter from the premises.
The installation could not proceed due to the damaged conduit.”

There is a conduit coming out of the external wall for the NBN connection. The technician tried to run a snake/fish tape through it and showed me that it had mud on it when he pulled it back out, so it sounds like the conduit may be broken, crushed, disconnected, buried, or not completed properly somewhere near the house.

NBN advised they don’t repair it because the issue is within the property boundary.

Does anyone have recommendations for someone in Adelaide who can inspect/locate/repair this sort of NBN lead-in conduit issue? I’m trying to work out whether it is broken under concrete, buried near the edge, or just not finished properly.

Any advice or recommendations would be appreciated. Thanks