Keeps ringing and ringing at least 20 times over the past few weeks.
Call back they don’t say who they are.
An agent will call you back when next I. Your area. SMS them to stop several times. Still keep calling and hang up when I go to answer

No reply when tried to call the missed call

Calling multiple times. When answered, not a clear voice saying from Synergy traying to install Energy Monitoring Devices. Asks if I have a smart phone, may be to install something. Sounds really doggy

Have received multiple calls from this mobile number over the last few weeks, sometimes several times/day. Never leave a message. Haven't called them back as assume is spam due to no message left. Recently received call from similar number but last 3 digits different, same thing, calls but no message left.

Caller: Unknown

Calling multiple times over the last few days. I never answer the phone to numbers I don’t know. No message left.

No message
They just call and call and call. Never leave a message. I never answer it or ring back .

Same as Terry. Keeps ringing

Called and cuts call, as I answer

Called multiple times in a day, delayed pick up like a call center number possibly.
Upon one returned call, got the voice mail "You may have missed a call from our research company, we'll try to call again when we're in your area" but does not state the name of the 'company'.

Call me several times a week always hang up no message left as don't answer unknown numbers. Have blocked but seems to keep morphing the number to avoid blocks.