Shortly after the release of Apple’s enormous new iPad Pro, reports started to surface claiming that the pricey device was running into problems when being charged. Now, the Cupertino company has published a document acknowledging that the tablets do sometimes freeze when recharging, and that Apple is working on a fix.

One iPad Pro user described the problem he was facing on Apple’s support forum last week. “At night it was down to 40% so I charged it and went to bed. When I woke up it was ‘dead’. It wouldn’t wake up. I needed to perform a hard reset to get it to come to life. Worked on it for a couple of hours and had to run an errand. Plugged it back in as I was going to need a full charge later that day. Came back to it, same thing. Dead. I needed to perform a hard reset to get it to turn on. Used it more, then last night plugged it in and this morning, same thing,” said forum member darkfire.shadows.

Although most of the reports say the issue occurs when charging the iPad Pro overnight, some users say it can take just over an hour for the tablet to freeze when it is plugged in and left alone. "I have the exact same issue. When I connect my iPad Pro to the charger for more than an hour, it goes dead,” wrote user LukeD.

Apple’s brief support document advises users facing this issue to force restart the iPad Pro by pressing and holding both the Sleep/Wake and Home buttons for at least ten seconds, until the Apple logo appears. It goes on to say that the company is aware of the issue and is investigating.

It’s not known if the problem is related to the iPad’s hardware, software, or a combination of the two. Both the 32GB and 128GB (Wi-Fi and LTE) iPad Pro models on iOS 9.1 have been affected.

This isn’t the first problem the iPad Pro has faced at launch; the Apple Pencil stylus and smart keyboard case accessories are delayed and will be released over a month after the iPad Pro went on sale. Furthermore, it was reported by The Verge that smaller developers are struggling to make the economics of the iPad Pro work.