Several calls trying to sell me home improvement services.  Seems pointless and a bit hinky as I live in a different country several hundred miles away.

probably spam or a collection agency regarding your telephone bill.  collection companies usually leave a message and identify themselves when they leave a message.  if you are getting a hangup, it's a gentle reminder to catch up on your phone bill.  Verizon usually does a day after you are a full month behind on a bill.

Calls and hangs up. Don't want them to bug me any more.

I keep getting calls from (613) 333-4568, they leave no messages.  You cannot call back.

I keep receiving solicitation calls from this number as well .many times they hang up on me . I have called my cell provider (sprint) and they have now blocked the number. Problem solved Its very annoying for these calls.