Error Failed to serialize to JSON: /config/.storage/core.config_entries

I have this log in my error. And so HA is not able to save new/changed integrations - every change is gone after restart. The json in this file has valid syntax. There is no “scan_interval” content. I also tried to remove the 8th array and also cleared the whole file - it did not solve this issue.
The 8th array is a ha mobile app.

Logger: homeassistant.util.json
Source: util/json.py:60
First occurred: 21:12:35 (1 occurrences)
Last logged: 21:12:35
Failed to serialize to JSON: /config/.storage/core.config_entries. Bad data at $.data.entries[8].data.scan_interval=0:05:00(<class 'datetime.timedelta'> 

I have this for some weeks, maybe months. I did not change content in file by myself.
Any advise how to fix this issue?

Did you enter 00:05:00 for scan_interval in one of your integrations? Try 600 instead (seconds).

Could be a combination of bad value representation and poor validity checks.

1-Wire integration is configured with scan_interval: 300. This does not seem supported anymore (not listed in docs). I removed the setting, restarted HA, no error in the logs. Thank you so much!