Facebook has halted sales of Oculus Rift and Quest virtual reality (VR) headsets to customers in Germany.
“We will continue supporting users who already own an Oculus device and we're looking forward to resuming sales in Germany soon," it added.
It comes as the German data regulator criticises the decision to require Oculus users to move to Facebook logins for their headsets by 2023.
Facebook purchased Oculus, a VR start-up, in 2014.
The annual Oculus conference, now called Facebook Connect, is due to go ahead in an online-only format on 16 September.
- from October 2020, new users can log in to their devices from a Facebook account only
- existing users will have the option to merge their Oculus and Facebook accounts – but they too will need to log in from a Facebook account from 1 January 2023.
The headsets will still work for users who choose not to log in at all, however.
But one game reviewer left a message on the company’s website, saying they would buy no more software for their Quest headset.
“I’m not OK with this,” one user wrote.
"I despise Facebook."
BBC News has contacted the Irish data protection authority, Facebook's primary data watchdog in the EU, for comment.