You’re seeing this error because draw.io cannot update its settings file due to a file system or permissions issue.
Try these steps:
Close all draw.io windows.
Go to C:\Users\diego.roman\AppData\Roaming\draw.io and make sure your user can write to this folder.
Delete any config.json.tmp-* files found there.
Temporarily disable antivirus, or try running draw.io as Administrator.
If the problem persists, check for disk errors.