https://genomebiology.biomedcentral.com/articles/10.1186/s13...:
“A programmatic scan of leading genomics journals reveals that approximately one-fifth of papers with supplementary Excel gene lists contain erroneous gene name conversions.”
That paper is from 2016, at least 12 years after the problem was first identified.
If you intended the data to be a string value, then it should have been enclosed in quotes.
Adding a ' before it should work, but for data extracted from arbitrary systems you'll have few guarantees of the sort. Formatting the cells in Excel to display the full value instead of the truncated value also works from memory, but you won't always know ahead of time if this happened later in the file.
In our case it was often mailing identifier barcodes so any loss of precision made them entirely useless.
It does this without any notification or warning when you save.