Rings twice, hangs up no message caller id undavailable,  calls approx. every half hour

Oh, they will keep calling until you answer the phone. Just tell them to put you on their companies do not call list and you shouldn't be bothered by them anymore.

573-388-2253 The number belongs to Tristate Water and Air Solutions. They sell water softeners and air filter systems. They call pretending to do survey's, just tell them you rent your home and they will leave you alone. If you tell them you own, then they give your number to someone else and they call you back trying to get you to do a free water or air test in your home so they can come and try to sell you a water softener system or air filter system.

573-388-2253 called at 1:30pm, left no message...then had an "unavailable" at 1:33pm...no voice mails...

Did you ever find out who this was that was calling I am getting the same call?

Has called several times. Rings twice, hangs up - no message. Screen says "unavailable"