This means you setup as noted and did not use it's WAN port.
I am running into folk that did not actually set up the router as a WAP and thus ran into your issue.
Here's the google that I use to refresh my memory on how to setup a router as an access point.
https://www.google.com/search?q=How+to+use+a+router+as+a+WAP
Also worth mentioning is once in a while someone drags out an old DSL modem to try this trick on. For me I call that unsupportable and may not help.
I have an all in one Modem/Router from my ISP (Hitron CGNM-2252). From that I'm running another router (Sagecom) working as an access point with the 2.4 and 5 ghz wireless frequencies turned off. My problem is I have a few smart devices hard wired to the sagecom and I cant remotely control them. I no there is a solution? Static IP, VPN?

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