Screen all incoming calls from unfamiliar numbers before picking up. This call pattern—ringing once then hanging up—often signals scammers probing for active lines to harvest and sell. No message left means it's unlikely legitimate; real callers usually leave voicemails. Block the number immediately to avoid repeated harassment, and report it to your carrier or authorities like the Do Not Call registry. Enable call-blocking apps for better protection against nuisance spam, which can escalate to more aggressive tactics if your line seems responsive.
They disconnected immediately, which makes me think they were just hunting for live numbers to sell.
No message was left.