If you're seeing the same notification twice, you might have notifications turned on in your regular settings and notifications turned on in the Budgeting & Spending feature (also known as Money Management or MX). To turn notifications on or off in Budgeting & Spending, go to Budgeting & Spending in the Money Management tab, then click the Settings icon in the upper-right corner.

Toggle the sliders for notifications you want to see or to remove, and choose whether you want email or SMS text alerts.