Node RED stop working

Hi everyone, I'm new on this technology, so sorry if it's a stupid question.
I and my partner are working for an university project, I made front end and she made back end. In a part of back end, she used node RED, specifically to insert data in MQTT, re-obtain these data and manipulate them in some way.
The problem is when we insert data with timestamp, node RED stop working, nothing change in cmd, but nothing works in the web window, deploy takes infinite time and we must close cmd. When we start again node RED and we go to http://127.0.0.1:1880/, nothing happens, the only solution is erase config folder of node RED.
We are desperate, how to fix this?
Thanks

What version of Node-RED?
What version of nodejs?
What do the logs say?

the only solution is erase config folder of node RED
what config folder?

If you think node-red is looping you can seart it manually using the -safe option to look at your flows.