Hello @Prabhat Singh ,
In my test, I cannot reproduce your problem.
For example:
1.Create a multi-line text column with “Enhanced rich text”
2.Switching from "Enhanced rich text" to "Plain"
Please confirm the following points:
1.Does the text entered by the user have style requirements? Can you provide your test text information?
2.Clear the browser cache for testing
3.Switch browsers for testing, such as IE, Edge, Chrome
4.Test on other lists
Thanks,
Echo Du
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