I have a database collection that I use to collect data from a stripe bank card payment form on my website. The idea is for users to add credit to an account id in a Wix database collection (based on the RFID of their tag). The "Amount" field on the form is where the user adds how much cash to add. I am having trouble getting the database field that the amount is writing to to cumulatively add the credited amount and not just overwrite the existing value. How would I go about getting the value to update the credit amount cumulatively instead of overwriting the value?