Why s3.to_parquet switching data types on publish to AWS Glue?

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I'm creating a dataframe like so: concatdatafile = pd.concat(datafile, axis=0, ignore_index=True, sort=False)

then checking some of the field data types before publish:

 logger.info("  *** concatdatafile['FS Seal Time (sec)'].dtypes={}".format(concatdatafile['FS Seal Time (sec)'].dtypes))
        logger.info("  *** concatdatafile['FS Cool Time (sec)'].dtypes={}".format(concatdatafile['FS Cool Time (sec)'].dtypes))
        

The next statement I have is a write:

response_wr = wr.s3.to_parquet(df=concatdatafile, path=s3_outputpath + 'full_data/', dataset=True,
                                        partition_cols=["MachineId", "year_num", "month_num", "day_num"], database='myDB',
                                        table='myDBTable', mode='append')

when I run this code in Glue, I get: log screenshot 1

(Note: I cleared out the glue definition before running, so it would have fresh metadata)

but in the Glue table, I'm seeing the fields changing types like so:
log screenshot 2

Question:...Why is it not respecting the data types I'm publishing? It sees the data looks like doubles (for now), but that's irrelevant. Later data will be strings, so I want it to not override the types I'm sending.

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