Oh yea, this has been one of the most common cases we have seen in support.

Microsoft Excel naturally, by default, tries to make your long number into scientific format.

Common impacted data: IC number, bank account number, and many, many others.

How do we solve it?

Simply select the cell where the scientifically noted number sits. And format the cell with Number format.
8.Turn-off-auto-scientific-notation

If you format a cell with the Number format from the Number format drop-down, then by default you will get two places after the decimal point.

To avoid the decimal places, you can use the Format Cells dialog box. Select Number option from the left window, and on the right window, make the decimal places to zero.
9.Turn-off-auto-scientific-notation

Another easy way to take away the decimals is clicking this button twice.
10

Enjoy importing!