To break your potty training so you can go back to wearing and using diapers you can try hypnosis for wetting your diaper.
Or also just simply start wearing diapers again and get rid of all of your underwear, boxers etc.
Then always go into the diaper for both pee and poop.
Eventually after 6 months or a year you should no longer want to use the toilet and will be unpotty trained.
I've heard of some people who have been wearing and using diapers for a few years and then they no longer think about when they need to pee or poop and just do it naturally in the diaper.
I know when I'm wearing a diaper I don't even think about the toilet and just pee in the diaper or go poop in the diaper when I'm wearing it.
When in underwear I feel the need to hold it and then go to the toilet but when in diapers I now just go pee or poop when needed.
Even before a full bladder when I'm in diapers I will just begin peeing the diaper whenever.
If you stick to wearing diapers all the time and using them then eventually you should forget about using the toilet.