how to change IG record from an item and pk with JS

Hi,

    I am on version 5.1.1.

     I have two fields one for the job_number (primaryKey) and another for how long it has setback in hours (changed to mins for the IG).

    Once the values have been validated I want to update the interactive grid column.

   I am currently updating the column using

      var view = apex.region(tableId).widget().interactiveGrid("getViews", "grid"),

      model = view.model;

      var record = model.getRecord(primaryKey);

       var fieldKey = model.getFieldKey(columnID);

      record[fieldKey] = value;

    I have also tried

    model.setValue(record, columnID, value);

  The value is inserted

But when I save the IG the value is set to null. It does however, say changes saved in the top right.

Any help would be appreciated.

Thanks