You have posted a large flow which I can't run as there are sqlite db nodes that I don't have installed. It isn't immediately clear to me which node in the flow is the date range node. Please post just a short flow consisting of just a few nodes that shows the problem. Also please post flows inline as described in this canned reply:
In order to make code readable and usable it is necessary to surround your code with three backticks (also known as a left quote or backquote ```)
```
code goes here
```
See this post for more details - How to share code or flow json
