The UnSaccoBello app keeps you logged in for 30 days, in compliance with current security regulations. Using the app every 2–3 weeks falls well within this window and should not trigger a new login request.
The issue is therefore likely related to your phone's local environment. The most common causes are: automatic cleaner apps that delete session data, automatic device or app updates, or using the app on multiple devices.
Please check for these issues, and if the problem persists, contact our support team.