Installed new commode 2 years ago. Since then I have replaced the flapper 3 times because of leak by. The hole in which the flapper sets over is on a angle instead of flat like I' am use to seeing. What can I do to stop this from leaking all the time?

Hi elmoinmd and welcome, me, I would change the flush valve out it may just be bad. Not too pricey or hard to change, If you decide to and need help post back and someone can guide you.

Make sure it is the right flapper. Some are brand specific.

II agree. REplace the flush valve correctly. Good luck, Tom

I agree with Parttime and Tom to replace the flush valve, it is cheap and easy to replace, Good luck.

John

How to Fix a Toilet - Flush Valve Replacement - Part 1 of 2 - YouTube

I had to replace a Kohler flapper once. Home Depot had rows and rows of guaranteed to be universal ones. Got all the way home and it didn't really stop the water. Went back and the Kohler ones were way above my reach and sight on the top row!

I was going to say Kohler but didn't know what they had. Yes, Kohler is different and so are some Mansfield's and American Standard.