There is an additional sheet in the bulk upload file: If there are multiple files the transaction will fail.
Presence of special characters in the amount column.
The second row is kept empty: The second row after the heading must have some value. If it is kept empty, the file will not get processed.
The file format is wrong: Stick to the format provided in the dashboard which is either .xlsx or .csv.
The details provided are wrong or the details are missing.