Sonoff R2 mini (ewelink) on HA

Hello, I am very new to this, I don’t really understand many things about HA, so don’t judge me lol…still learning…right now I have HA running on rpi 3 model B, at first I needed it just for controlling light switches (sonoff r2 mini relays, with ewelink software), it was fine, everything worked fine, but however, my isp sucked, so I got a better isp and new router, I could not find how to transfer the old configuration to a new router, so I had to manually reconnect all of my relays (there’s like 20 of them…), the good thing was that my home was still under construction, so most of my relays was still reachable, because in order to pair them - you need to press the switch on the relay, so I did all that, reinstalled HA to new sd card and it worked fine, but only with ewelink app and it still does work that way, I cannot use it using HA, I tried to refresh, deleted it off the main screen and tried to upload it again, but still can’t use it, it says “Failed to call service switch/turn_on. Service not found.”. So my questions from all of this are:

  1. Is it possible to somehow save the configurations of already paired relays that control the lights and then upload them again? Meaning - is there a file with all of the relays macs that I could save and then let’s upload to a new network with a new router? or if that is not possible - could I change new routers ip to match the old one? and would it work then?

  2. How to solve “Failed to call service switch/turn_on. Service not found.” ?

thanks for reading all that