Apple (AAPL) released an update to the iPhone 5 this week to fix a data bug that was affecting Verizon Wireless (VZ) subscribers, who were being charged for using cellular data even when they were connected to a Wi-Fi network. The issue was considered fixed by Monday morning, but a number of users are reporting similar problems on other carriers, 9To5Mac reports. An unconfirmed number of AT&T (T) customers are experiencing similar data issues and seeing hundreds of dollars in cellular overage charges, despite using Wi-Fi for most of their downloads. AT&T did not immediately respond to requests for comment.

UPDATE: Users are reporting that the data bug is also affecting iPads operating on AT&T’s network.