Adding a device into Home App

I have a smart plug added into the Home App. I recently switch my WiFi router and the plug showed as not responding. I tried updating the WiFi on the smart plug via its own app, but Home App still shows “not responding”. I the decided to remove the accessory into the Home App and tried to add it again from the smart plug app but it says it is already in the Hone App but now it is not showing up. What can I do? I don’t know if resetting the smart plug would even help since the Home App is the one that seems to be reporting that it is already added but not showing it.