Sunday Times order & payment acknowledged. But no deliveries for 8 weeks, despite notification

While away from home in February 2021, I received by email a most attractive offer to subscribe for 6 months, and paid in full for this. On return to my home late in March, it appeared that no issues had been delivered.

I promptly emailed the email address *** that acknowledged my order (and advance payment in full) about the non-delivery, but the email was returned to me.

Also, since then I have received no deliveries. I emailed both *** and *** today, but this email was also returned by the Mail Delivery System