iPad time is losing accuracy

Some other items to check are:

• The most recent iPadOS should be installed
• That your iPad has an Internet connection regularly
• That the battery is never completely discharged
• That Airplane mode is not enabled
• That the Time Zone is correctly set to your region by either setting it manually, or by using Set Automatically and ensuring that "Setting Time Zone" is permitted in Settings > Privacy & Security > Location Services > System Services.
• That no profiles are listed under Settings > General > VPN & Device Management

One last consideration would be if the iPad is using cellular or WiFi for its internet connection. If it is using cellular data, then the network time from your carrier should be correct at all times. If, however, you are using WiFi for Internet connectivity, then it's possible that any router/gateway device between you and the Internet is for some reason interfering with the NTP protocol.

If you have customized the firewall settings on your home network, please ensure that the NTP protocol is allowed (UPD port 123). In addition, using a VPN can also affect getting an accurate local time from a time server.