Why doesn't IP come from the provider?

Question

D-Link

They built a bridge in a rather difficult terrain (hilly, elevation difference up to 50 meters). One thing did not work, they stuck two bridges assembled on the knee from the Ubiquiti NanoBeam M5-400.
It works like this:
skyscraper with optics →
bridge #1 ( nanobeam #1 → nanobeam #2 ) →
bridge #2 ( nanobeam #3 → nanobeam #4 ) →
client ( zyxel/d-link dir-615 ).
Those. bridges are connected in series. Further, having endured installation in the cold, there was a plug. We stick a twisted pair cable into a laptop - everything that is needed arrives from the provider via DHCP and the Internet works with a whistle. We are trying to plug the wire into any of the Wi-Fi routers, which is long, which is zukhel - zero emotions, neither one nor the other works. Zuhel in the logs is generally silent in principle. Dlink (configured to Dynamic IP) says "Dynamic IP. Unknown error".
What is it connected with? How to win?
UPD #1: Evgeny Bychenko is called

Answer 1

=)
You need to see what arrives on the interface. To do this, you need to remove the traffic dump, if possible. If frames from DHCP arrive \ packets in general from the side of the dip - then dig what arrives in them and what kind of trouble with poppy binding or etc. If it is clean at the link level, then the problem is in physics - we dig bridges, check whether everything was bridged correctly, if the link was lost somewhere, or whether the coordination of the speeds of both the copper and the radio path was correct.

Answer 2

if Provo does not have a poppy binding, copy the poppy from the laptop and drive it into the routers