Not one ancient manuscript is exactly like another, all have “variants” or differences. After all, all ancient manuscripts were copied by hand, and no human hand is perfect.
What kind of mistakes are there in the ancient manuscripts? Only small and unimportant mistakes, the kind one makes when copying something. And when copying by dictation, most errors are simply attributable to mistakes in hearing, such as “b-r-e-t-h-r-e-n” being misspelled “b-r-e-t-h-e-r-n.”
All biblical scholars agree that the vast majority of textual variants are “trivialities,” small and unimportant differences that do not affect in any way the true meaning of Scripture. Besides, with the thousands of ancient manuscripts to compare with one another, textual variants are easily detected and corrected.