Error on importing zip files "Cannot import values with sql"

We are having a new problem when we import csv files (in a .zip archive) to any of our apps. On import we get a green success message, but the upload hasn’t happened and the file IMPORT_DATA.log says: "cannot import sql error. The import log contains an entry like this for each line of data that hasn’t uploaded namely:IMPORT_DATA Cannot insert values with sql: com.mysql.jdbc.JDBC42PreparedStatement@40bb1369: INSERT INTO BD0781FE-AEF5-99A8-FF85-80DFCC400700_rel VALUES ( ‘12AC1DC7-C11B-D36D-FFB0-0ED60B875B00’,‘7868BA60-56AC-BEA8-FF3D-98F112574500’,‘8CBF116D-D211-CFEB-F.AE56763D-61DC-8C28-F.62D65’ ) ON DUPLICATE KEY UPDATE null=null
Upload templates and protocols are unchanged from those we have used successfully on all our apps up until last week.

NB manual upload of one item at a time via the console is continuing to work fine.

We first noticed the error last week. All our eight apps work the same (we have tested with three and the error occurs on them all).

Client SDK (REST / Android / Objective-C / Swift / JS )

Not sure.

Application ID BD0781FE-AEF5-99A8-FF85-80DFCC400700.and seven others

Expected Behavior

Please describe the expected behavior of the issue, starting from the first action.

1.Import csv file in a zip folder Students.zip
2.Get a green success flash in top right of screen
3.Data is uploaded

Actual Behavior

1.Import csv file in a zip folder Students.zip
2.Get a green success flash in top right of screen
3.Data is not uploaded.
4. Go to Files>Import>Import_DATA.LOG, find message as above

Reproducible Test Case

Please provide a simple code that could be run in a new clean app and reproduce the issue.

If the issue is more complex or requires configuration, please provide a link to a project on Github that reproduces the issue.

Hello,

This problem should be fixed now, please verify.