asuscomm address still online after disabling DDNS

[Ojee]

For a few years I have used a free asuscomm address via the DDNS client on my RT-AC87U. I have stopped using this DDNS service but after several months the address is still linked to my IP, and I can still access services through it. It's no big deal, but I don't need it anymore. How do I get rid of it?

 

[L&LD]

Stop using it. And If you still have the RT-AC87U, remove it from the router.

 

[Ojee]

I already have stopped using it. It just won't go away.