REST API file upload seems to fail if the field name is too long

REST API file upload seems to fail if the field name is too long

I tried uploading a file of about 1.7 MB to a field using the Zoho REST API, specifically to the URL to https://creator.zoho.eu/api/xml/fileupload/ but I got back the error {"code":2945,"message":"MORE_THAN_MAX_LENGTH"} which is a JSON response, interesting.
I was able to fix the problem by renaming the filed, it seems that if the field name is too long then the upload files which is a bit of a cryptic error message.
The original field name was Financial_Information_Please_upload_your_certified_lease_agreement I then changed this to
Lease_Agreement_Upload and it worked, this was using the exact same file both times. I changed it back to what it was and the same error happened.