Fitness tracking firm Fitbit has just halted the sales and issued a voluntary recall of its wristband activity tracker Fitbit Force. The move comes after some users complained of skin irritation from prolonged use of the product, according to TechCrunch.

The California-based company had initially offered a refund for affected users, or a replacement with another tracker. However, Fitbit has now gone on a full-scale product recall.

James Park, the cofounder and Chief Executive Officer (CEO) of Fitbit, posted a letter about the issue. He cited an independent study which named the skin problem as allergic contact dermatitis. The study said the skin irritation probably resulted from physical contact with trace amounts of nickel or the materials used in making the product, the report explained.

Part of the company's announcement read: "While only a small percentage of Force users have reported any issue, we care about every one of our customers. We have stopped selling Force and are in the process of conducting a voluntary recall, out of an abundance of caution. We are also offering a refund directly to consumers for full retail price. We want to thank each and every member of the Fitbit community for their continued loyalty and support. We are working on our next-generation tracker and will announce news about it soon."