Barclays Bank connection error 101

I am using QBSE and have had my Quickbooks account linked to my Barclays Bank account for some time. For the past couple of days I have been getting a connection error code 101 with advice to try again in a couple of hours but it has not resolved. I have tried connecting using several different browsers (Safari, Google Chrome and Firefox) but receive the same error code with all three. Any advice on how to resolve this please?