Hi and welcome to the site, I’m Louie. Sorry you had to wait awhile but I’ll do my best to help.
Initially, bear with me; describe what keys are used to set the date and time.
Additionally, is the "Caller ID" feature enabled?
Please try keying in MENU # 2 2 6 and select "Manual" instead of "Caller ID Auto".The described issue is caused by callers with different time settings in their phones. The KX-TGL460 keeps on trying to snc with the caller's time setting.