Why is Ps4 shutting down with wifi usage?

I recently bought a refurbished PS4 on Amazon. The first few hours were fine, so i tried downloading a few games on standby. I noticed that it would shutoff completely after a few minutes. I thought I had made a mistake, but I noticed that the problem would continue even during gameplay and began to shut off. I initially thought that the shut-off was random, but I eventually noticed it wasn't. My PS4 shuts off when the WiFi is used. I've tested with and without internet connection, on both WiFi and Ethernet and it only happens when on WiFi. The ethernet connection works fine. However I don't have a long enough ethernet cable to reach for my PS4. Is there a way to fix this issue without buying 60$ in cables or buying a new system?