We in the US have the same issue.

QB IDs are listed on several spam lists, when QB uses those particular IDs to send invoices/POs they will not go through. This issue is known since early spring but QB seems not to be able to fix it. There is another tread you might want to follow: https://quickbooks.intuit.com/learn-support/en-us/other-questions/re-intuit-ips-found-in-spamcop-blo...