How to clear existing “sticky” DHCP cable parameters in order to connect to another DHCP server?

I have 3 Gl-iNet routers with the following IPs:

Router (A):

Router (B):

Router (C):

Router (C) was previously connected with a cable to router (A), thus showing under “cable” the DHCP parameters used to connect to router (A), thus gateway and DNS server:

Now I have decided to change the connections: I want router (C) to connect (with cable) to router (B) ( I connect the cable to a LAN port of router (B) and the WAN port of router (C). Unfortunately the cable parameters for the DHCP connection stay in a “sticky” way pointing to router (A) instead of router (B) !

I have tried to change from DHCP to STATIC, entering parameters for router (B), and the settings are successfully modified. But, when I change the cable settings back to “DHCP” instead of static, the “sticky” values for router (A) appear again. The repeater connection is pointing to router (B), but the cable connection “wants” to keep connecting to the original connection to router (A).

Is there a way to CLEAR the existing DHCP parameters (in the example router (A)) in order to allow a new detection of the new gateway when the router is connected by cable to another router ?

Actually the router should just get new DHCP IP.

So your issue seems rather strange.