There is a limit of the number of call log entries and message log to 5,000 calls and 2,000 SMS messages. If you reach the limit, you will receive a notification that guides you to set up an auto clean mechanism, which automatically deletes old records from the log.
You can set up automatic cleaning by confirming the alert you received, or by logging into the Log / Log screen and clicking a  button in the top right corner of the app and setting auto clean mode.
Once you have set up the mechanism, it will automatically run and schedule record clearing at regular intervals.
Tags # Alert # notification # restriction # call log # SMS log # log # restriction # limited # cleaning #auto clean # auto-clean