My iphone 5 isn't connecting to the PC or being recognised by itunes

My iphone 5 isn't connecting to the PC or being recognised by itunes

Added (1). It isn't the cable or the PC as other devices mainly an iphone 6s and an ipad air 2 seem fine. I've very recently updated to ios 10.3.3 and this is happening since then. I've tried to contact apple but nor response… What should i do

Is my phone iCloud locked?

I recently purchased an iPhone 6 Plus with a locked passcode for a decent price. The seller tells me that it's not iCloud locked but here's the the pop-up.
On the main screen it reads:
"! APPLE ID VERIFICATION" "Enter your Apple ID password in Settings"

IPhone 5s, trying to troubleshoot problem?

I have a 32gb iPhone 5S, bought in 2014. It was fine up until July 2016, when I decided to try the iOS 10 beta. When I restored back to iOS 9 I ran into a problem that I still hadn t solved today.
The problem: The iPhone constantly says searching…, ICCID is gone in the settings and modem firmware is blank. IMEI and MEID is still there, however. Battery drains significantly worse, even on airplane mode. (It's the main problem because I no longer use it as a phone, more of an iPod).
Whenever I restore it, by putting it into dfu mode, an (error code -1) pops up on iTunes, and I'm unable to restore. I will proceed to restore until it successfully does so. When I'm successfully able to restore, the iccid and modem firmware will be there in the settings. However, after a few days, the ICCID will again disappear, followed by the modem firmware if I reboot the device. The battery drain occurs as soon as the iccid disappears.
I've tried removing the SIM card when I finished setting up, after restoring, but it makes no difference.
Also other problems that may or may not be related: the flash and rear camera no longer works. I'm not sure when they broke but I find it odd how they broke simultaneously.
I'm also unable to update OTA because "an error occurred while installing iOS 10.x.x.
I'm not going to bring this into apple to fix. I just want to know the problem.

What is the solution for the date/time error on iPhone 5c?

I just recently got an iPhone 5c, and it works amazing it's basically brand new out-of-the-box. But for the life of me, I can't figure out why the date and time is off. I've tried both bowl resets and I've tried going into date and time settings to reset it. I've tried going back-and-forth between manual and automatic detection, but nothing seems to be working. Someone please help me.