A mysterious ‘Error 53’ message is responsible for killing “thousands” of iPhones since iOS 9 launched last Fall. The error only seems to affect the iPhone 6, and only handsets which have had third-party home button repairs. But if you’re in that unfortunate bracket, there’s no way to fix it.

The Guardian reports that many users who have had otherwise successful repairs by unauthorized technicians, in some cases using their iPhone for months afterwards without issue, soon find that upgrading to iOS 9 “permanently disables the handset” with no prior warning. And they’re not happy about it.

Apple itself can charge several hundred dollars to fix a faulty home button, so it’s no surprise that many iPhone 6 owners have chosen to pay a third-party service for repairs. But those unofficial fixes seem to be causing problems further down the line. Many are suggesting Apple is refusing to sort this problem to push independent repair shops out of business and encourage more users to go down the official route for their fixes.

After keeping quiet for months, an Apple spokesperson recently admitted that the issue is known. It’s apparently due to the increased security measures brought in with iOS 9. The “secure enclave chip,” unique to each device and paired to the Touch ID sensor to protect fingerprint data, can potentially be compromised by third-party repairs. To protect customer privacy, “the pairing is re-validated” when any hardware changes are made to the home button. If that validation fails – a practical certainty without an official Apple technician – the device is disabled to protect the user’s personal data.

Read more: what does Apple do with our personal data?

Though the mysterious ‘Error 53’ has been around for several months, the story is just now picking up steam – and it isn’t over yet. It will be interesting to see how Apple reacts if the complaints really start to stack up. We would expect Apple to stick to its guns regarding privacy at all costs, but it would be nice to see the company cut a little slack to those who have been left iPhone-less through no real fault of their own.