If you are working in the IR10 and click Save, and encounter the error Failed to save the return: Failed to Fetch, the data entered has not been saved. Our development team are working on a resolution for this issue. In the meantime please use this workaround:
Refresh the web page (F5). Note: Any recent data entries will be lost.
Add any attachments required to the return.
Save and enter in the data.
If the problem persists, delete the attachment, Save return, then re-add the attachment and continue working.