I’ve already declined the premium membership, yet the upsell pop-up appears every time I log into my account.

Seeing the same modal on every login is beyond frustrating and seriously degrades the user experience. Once a user says no, that choice should be respected for more than a single session. Repeating it at login doesn’t encourage an upgrade, it creates resentment.

Right now, the constant interruption makes me consider canceling my account rather than upgrading.