import does not says invalid file
Have no idea what you are referring to.
Import of Bank staement in CSV, comma delimited file gives error, Invalid File v20.2.86.
Have you read this Guide: https://www.manager.io/guides/9240? Make sure the file you are importing is really a CSV file, not in your spreadsheet’s format. And make sure number and date formats in the imported file match your preferences in Manager.