Stephanie Ley said she found piles of letters from the insurance company stashed in her mailbox between Thursday and Monday.
"A week ago on Thursday was the first wave of letters, I received 46 letters," she told CNN. "I immediately called United Health Insurance and told them I had received 46 letters with the same letter."
And the letters are just kept coming, piling up to at least 500 Monday.
The letters are about $ 54 or $ 0, which health claims says United Healthcare is not covered said Lay.
When she asked United Healthcare why she was getting a mountain of letters, she was told it was a coding problem, she said.
In a statement, United Healthcare told CNN that it was working to resolve the issue but could not provide details because of confidentiality requirements.
"We have identified the cause of the problem. We are very sorry that this happened, and we have contacted the family to discuss the situation with them," said the health insurer.
Lay said all letters had a message at the bottom urging people to go paperless. "I think they had to cut down half the forest just to send it," she said.