While there have already been reports about replacement Samsung Galaxy Note7 units overheating in South Korea, a new Wall Street Journal report now says that similar complaints have been received by the company in the US as well.

In many cases, users have complained that the phablet gets very hot during calls. For its part, Samsung has acknowledged the complaints and has said that it’s investigating the matter. The company is, however, assuring users that the issue “does not pose a safety concern.”

“There have been a few reports about the battery charging levels and we would like to reassure everyone that the issue does not pose a safety concern,” the tech giant said. “In normal conditions, all smartphones may experience temperature fluctuations.”

The South Korean firm also said that it’s focusing on each case separately and trying to get it resolved through its customer service and warranty process.