We used Klaviyo for years (and Shopify Email for a few months) in the past, then last month migrated our 70k+ subscribers to Brevo (on a shared IP). After weeks of setup, we sent out our first email campaign today (essentially using the exact same setup as before: validated domain, a list with proper subscribers only - that we actually cleaned before migration).
Our campaign today got 6% open rate, that might climb up by 9-10% by the end of the week, but nowhere near our previous fairly standard 30-35-40% open rates.
After this, our account got suspended and will be permanently suspended if it happens again despite we paid for a whole year last month.
I was just wondering what do I need to check to resolve this ridiculously low open rate, does anyone have an idea why this has happened?