Samsung Electronics Co Ltd is retrieving all Galaxy Fold samples distributed to reviewers to investigate reports of broken screens, a day after it postponed the phone’s launch.

Reuters reports that the retrieval comes as the world’s biggest smartphone maker met with embarrassment ahead of the foldable device’s U.S. release on April 26, with a handful of technology journalists reporting breaks, bulges and blinking screens after a day’s use.

The South Korean tech giant postponed the handset’s launch for an unspecified period of time while it investigated the matter.

It said initial findings showed the issues could be associated with impact on exposed areas of the hinges.

A person with direct knowledge of the supply chain said KH Vatec conducted an internal review of hinges used in the Galaxy Fold and found no defects.

In March, Samsung released a video showing robots folding Galaxy Fold handsets 200,000 times for its durability test.

In some cases, reviewers had peeled off a layer of film which they mistook for a disposable screen protector.

“It’s disastrous that Samsung sent samples to reviewers without clear instructions on how to handle the device, and that the firm needs to fix screen flickering,” said analyst Kim Young-woo at SK Securities.

One Samsung employee, speaking on condition of anonymity, said, “On the bright side, we have an opportunity to nail down this issue and fix it before selling the phones to a massive audience, so they won’t have same complaints.”