NEED ADVICE!!!: Should I pop up on him?

So I am seeing this guy for about Five weeks now. We Text, talk, or FaceTime every day, I see him multiple times a week. I know that he likes me without a doubt. And I like him too. So his phone has been messing up a lot lately. It turns off out of nowhere and He has to just wait for it to come back on to use it. I have actually seen it happen. I haven’t heard from him all day yesterday which is weird because we talk every day. If I don’t hear from him at all today should I pop up on him at his apartment and check up on him? Or should I hit up his sister on social media to get in touch with him? Honestly, I’m starting to miss him and I wanna talk to/see him even though it’s literally been a day since I haven’t spoken to him and two days since I last saw him.

Edit:How I know his phone isn’t working right now is because when I text him the message does not send and when I call him it goes straight to voicemail.