My lambda function is unable to unzip a file

I deployed a flask app to lambda that includes a function that unzip a small file (124ko), but nothing works as expected. The unzipping clearly fail and I can’t find the reason.

2021-03-23T12:12:46.346+01:00	error [/tmp/39423ff39f7f4378a8f835a20fdcb688.zip]: missing 3183398882 bytes in zipfile

2021-03-23T12:12:46.346+01:00	(attempting to process anyway)

2021-03-23T12:12:46.346+01:00	error [/tmp/39423ff39f7f4378a8f835a20fdcb688.zip]: start of central directory not found;


2021-03-23T12:12:46.346+01:00	zipfile corrupt.

2021-03-23T12:12:46.346+01:00	(please check that you have transferred or created the zipfile in the

2021-03-23T12:12:46.346+01:00	appropriate BINARY mode and that you have compiled UnZip properly)

There is no problem when testing locally and the zip file is okay. So I guess the issue comes from lambda.

The code :

with open(file_path, "wb") as binary_file:
        binary_file.write(file_content)

Expected behavior : The file should unzip without problem just as it does when the app runs locally or in heroku.

P.S. : I am using postman for testing .

Any suggestion ?