Apple is having trouble getting a new fingerprint sensor working for an iPhone model this year, which could ultimately lead the company to eliminate it and opt for an alternative, Pacific Crest Securities analysts wrote to investors on Sunday. According to the analysts, whose comments were earlier reported on by Investor’s Business Daily, Apple had hopes of bundling the fingerprint sensor inside its iPhone’s screen, but the component isn’t working as the company might have hoped.

Apple (AAPL) has been rumored for months to be working on a major iPhone update this year that would include a new, all-glass design. Apple might also eliminate the handset’s bezels, creating an edge-to-edge screen like Samsung’s recently announced Galaxy S8 and S8+ devices.

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The rumored design, which would essentially turn the iPhone’s entire face into a touchscreen, would also force Apple to remove the physical home button that has sat beneath the iPhone’s screen since its initial release in 2007. Several rumors say Apple plans to create a virtual home button that would live inside the smartphone’s software, iOS, and use an optical fingerprint sensor baked into the iPhone’s screen. A user would place their finger on the iPhone’s screen to authenticate mobile payments and unlock their devices. The sensor under the screen would ensure it was the authorized user’s finger and allow the transaction to complete.

Samsung was rumored to be considering the same feature for its Galaxy S8 line. However, weeks before the smartphone’s release, rumors surfaced, saying the technology wasn’t working properly and Samsung was forced to offer a traditional, physical fingerprint sensor in the device. When the Galaxy S8 launches on Friday, it will indeed come with a physical sensor on its rear panel.

In their note to investors, Pacific Crest analysts said that their supplier checks suggests Apple’s “fingerprint module provider” doesn’t yet have “firm orders for production.” The analysts believe the lack of such orders means Apple doesn’t think the fingerprint sensor technology is “ready.”

Apple could delay the iPhone’s release over the sensor, the analysts said, but they don’t believe a delay would be enough to negatively impact Apple’s smartphone sales.

Alongside Apple’s newly designed smartphone—which could be known as the iPhone 8, iPhone X, or iPhone Edition—the company is expected to deliver minor upgrades over last year’s models in two handsets rumored to be called the iPhone 7s and iPhone 7s Plus.