This is the way collections work and is not a bug. A collection brings together data from more than 1 account. In the case you are describing you must have a balance in another account on the date in question that is also included in the collection. For example, imagine a collection called "House Equity" which has the accounts "House Value" and "Mortgage" as members. To start with let's also assume that balances exist for both accounts on 8 Dec 2019, 15 Dec 2019 and 14 Jan 2020. The collection will show a balance on all 3 dates : the sum of the balances of each account on these dates. Now assume you deleted the balance on 15 Dec for the Mortgage account only. The collection will still show a balance on 15 Dec : the sum of the balance on 15 Dec for House Value and the previous balance for Mortgage (the one from 8 Dec in this instance). You would need to also delete the balance in House Value on the 15 Dec for that date to disappear in the Collect