Avast Cleanup Premium - keeps badgering me with 60% off

I cancelled the free trial some days before expiration - that went OK.
But now, almost every time I reboot, or come back from hibernation, etc, I get a popup saying “Your Avast Cleanup Premium trial is over. Buy now to keep your PC clean and tidy again - and we’re offering you 60% off to make that happen”.
The only button I can click says “Buy Now”. So I close the popup window. And then (sometimes immediately, usually a while later) it pops up again.
Please tell me how to stop it - it’s beyond irritating.

Hi, you need to uninstall ACP.

Thank you! I’m ashamed I hadn’t worked that out myself…

You’re welcome.