So you have a 10.0.1.x from your ISP, then have a 10.0.0.x for TP Link, then your UXG is creating a third 10.0.1.x behind the TP Link? There is either a collision between the USG and ISP router both using 10.0.1.x for their networks, or you are trying (incorrectly) to span a 10.0.1.x across both devices, but the 10.0.0.x network is in the way/not routing the traffic.
You will either need to build out the routing tables manually (pain in the ass), or correct your network topology. Start with a network diagram, and make sure you know what NAT means/the difference between routing and switching.
Ideally, your UXG would be the only internet-facing device, and would replace your ISP router directly, but this isn’t possible with most home ISPs. Your TP Link and any wireless APs would be in switch/bridge mode behind the UXG, and not creating a new network (routing).
Not sure of your level of routing knowledge, but assuming you don’t know, just setting your UXG to 10.0.1.0/32 will not make it the “same” network as your ISP router— it will try to create a new network in the same address space, unless you specifically set it to bridge/switch mode/disable routing/creating a network. And if you do this behind the TP link, you would need to create a static route to span the networks, but I don’t think this is what you are trying to do.
I think your issue with the UXG not working on your ISP router’s network directly is that both your ISP router and the UXG are creating/acting as the “gateway” on 10.0.1.1, resulting in a collision. Set the UXG to run as a bridge, or create a different network (10.0.2.0/32) while operating on the ISP subnet (10.0.1.0/32).