With these kind of setup, it's possible that this is caused by an IP address conflict. As far as I know, TP Link routers are also using the same IP address as the Linksys which is 192.168.1.1. The Dlink routers still work because it's using a default IP of 192.168.0.1 which is not in conflict with the TP link. So I suggest, you change the local IP address of both Linksys routers.
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