When is a creditor calling you considered harassment?

My husband and I refinanced our mortgage for a lower rate and shorter term. We pay bi-monthly (1/2 payments every two weeks) so that we pay off our house quicker. We ve done this for years even before refinancing. We closed on our new terms months ago and since then we keep getting calls saying our bank hasnt received our payment. These come from a third party representive. Of course we have paid, but for some reason since refinancing, they show we aren t current because of us making the bi-monthly payments. This was never an issue before.
I ve contacted our branch who then called someone else to sort it out and they were told that the calls were only temporary and after the first month they would stop. They haven t.
These people call and we explain to them the circumstances and they say they ll put a note on our file so no one calls back but then they do the next day. They call on weekends and at night when Im putting my kids to bed. It s frustrating because our bank can t seem to get it together and my husband and I are the ones suffering.
At what point are these calls considered harassment? We aren t behind in our payment. We are never late as the payment comes directly out of our account. This is just a mistake on their end, but it seems to be one that no one is able to fix. What can I do to get these calls to stop?
I appreciate any considerate feedback

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