Just received the reply of Auctiva Support:
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Hello George,
Thanks for contacting us regarding this matter, and I’m sorry to hear about the trouble you are having. This is a known issue to us and our engineers are working to resolve this as soon as possible, but that no ETA is available at this point.
We apologize for any inconveniences this issue is causing. If there is anything further I can do to assist you, please don't hesitate to ask!
Sincerely,
Auctiva Support.
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As you see, there's not much we can do but wait.