I have a nasally voice. I think it is a lisp. I watched videos regarding my problem in youtube and also researched few things about it in ChatGpt. I came across a therapy where I have to pinch both nostrils so that air doesn't blow out of my nose and practice saying words containing 's' sound. Doing this therapy I came across another problem which is known as minimal pair. When I pronounce some words like 'this' - 'these', 'sip'-'ship', any many other words I can't differentiate much. Due to the muscle memory, I can't see improvement only while i am doing therapy and after that I again start doing same pronunciation mistake and the air blows through the nose. I am very insecure about my voice. So if any of the doctors here could give solution to this problems, it would be really helpful