Suspicious activity
i am receiving calls claiming to be apple support saying there are some suspicious activity with my iCloud acct
It is a scam. Apple doesn't make unsolicited phone calls. If there was a problem you would be notified when attempting to log in, including when logging into this forum. Also see: https://support.apple.com/en-us/HT204759
One option to consider is Settings > Phone > Silence Unknown Callers. See: https://support.apple.com/en-us/HT207099