Screen Garbled Lossage Unasked-for Search
If C-l shows that the text is wrong, try undoing the changes to it using C-x u until it gets back to a state you consider correct. Also try C-h l to find out what command you typed to produce the observed results.
If a large portion of text appears to be missing at the beginning or
end of the buffer, check for the word `
Narrow' in the mode line.
If it appears, the text you don't see is probably still present, but
temporarily off-limits. To make it accessible again, type C-x n w. See Narrowing.