Macbook Exel file has gone my data, anyone can help?

Question

Below are the erro.

Excel cannot open the file ’~$JENJAROM AND KAPAR 2 copy.xlsx’ because the file format or file extension is not valid. Verify that the file has not been corrupted and that the file extension matches the format of the file.

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The file format and extension of ’~$JENJAROM AND KAPAR 2.xls’ don’t match. The file could be corrupted or unsafe. Unless you trust its source, don’t open it. Do you want to open it anyway?

i had follow chg the file name from .xlsx to .xls

pls help me, i had work 3 days 3 nights for the data, now totally gone.