Hi @Research,
An "Invalid update" error message is typically displayed when one or more fields on the form view have an invalid value in it. Essentially, a field causing the error either does not support the inputted value or is unable to create a reference in the case of reference fields.
Whilst it sounds obvious, the fix is to add a correct value to the erroneous field.
Or as a workaround, you can remove the field from the view.
Based on your screen shot, it looks like the Assignment group is Mandatory but doesn't have a valid value, or it's empty but the system believes it's populated as the asterisk next to it to signify it's mandatory is not red.
Try change the Assignment Group value to ensure it's populated correctly.
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Thanks, Robbie
