Sales Receipt Error - 'We were busy working out the VAT but didn’t quite finish calculating it. Save your invoice again.'

Hello, I hope the community can help me figure this problem out. I tried Quickbooks support, but after finally navigated past the god awful AI Bot to a support agent, after 20 minutes of the agent taking 3-4 minutes between replies, and enduring drivel questions of ‘how’s the day going’ and then having the audacity to ask if I am still there when I ignore the drivel questions I gave up!    Sorry, I am ranting I know, I am a nice guy really, just Intuit really do frustrate.  :) 

Anyway, the real issue if anyone can advice, for around 4-6 weeks now (since the new awful layout was forced upon me again). when entering Sales Receipts, more often than not, after i press the submit button it will freeze and then it comes up with the error 'We were busy working out the VAT but didn’t quite finish calculating it. Save your invoice again.' - Clicking submit again always immediately goes through.    From the dozen or so I entered this morning the error came up 3/4 times. We are not VAT registered, and it’s random happening too.

Where it becomes a problem, if I don't pay attention I move away from QuickBooks window thinking I have submitted a sales receipt, only to find ages later when I return it didn't go though and the error message is there.

Any thoughts?     Thank you.