Received call from (415) 367-1621 at 12:20PM PT, no message left.  Other reverse lookup sites report telemarketers.

Receive a call from them @ 6:30pm.  NO message left.  Also by phone # said SSI.  No message I don't trust you.

Just received a call from this number, if this is a call from "SSI", why would they call on a weekend, this late and without leaving a message.  It's obviously one of those scam numbers.  If you don't know any number, don't pick it up.  If they don't leave a message, don't bother calling them back.

SSI = "Survey Sampling International (415) 367-1621 US"
Google that!
https://www.surveysampling.com/general/received-a-call

"Thank you for calling SSI. We are an independent survey research organization. If you were contacted by us to answer some questions, we ask for your participation. Your opinion can influence manufacturers, service providers, and politicians. It is your opportunity to be heard. Your information will be kept confidential, and your individual answers will not be distributed without your permission. If you would like to know more about SSI, please go to www.surveysampling.com. Thank you."

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