Thank you for reaching out to the community. We're sorry to hear that your phone's been having a problem. We know our customers rely heavily on their devices, and we want to help in any way we can. No, there are no current issues with the iPhone 5S. Its on the older side, so it could be a simple device failure. However, before we write the phone off, I would recommend trying a few things. First, I'd press and hold the power/sleep button as well as the home key for up to a minute. Generally, this will wake the phone up if there's a simple software glitch. You can release those keys if it begins to light up. As a final option, you can also attempt a recovery mode restore, which you can learn the steps for here: http://apple.co/1diJJl8 The phone starts in the off status for this process, so you'll still be able to try it. Be advised that this second option does clear a phone out, so if it works, the phone will be wiped clean of any and all content. You'd need to recover it later through a backup you already have. If neither of these things work, it will be time to review replacement options. Customer service will be able to answer any questions you may have about those. I hope this helps.
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