Setting up Easystore for writing files from a Mac to later be read from Windows

Hi. I recently purchased a 4TB Easystore portable drive (not the MAC specific version).

I have reformatted the drive to EXFAT because I want to write files to the drive from my MAC but I would also like to be able to read them from a windows machine later on.

The Mac (macOS Catalina Version 10.15) recognizes the easystore drive but the permission is set to “read only” and I cannot change it. When using the same drive on a different mac with Mojave it does allow read and write. What to do???

Thanks for your help!