This usually indicates your storage is very very near maximum
It will cause issues in the long run if you do not clear it up,

1. Clear up your phone storage
2. Reboot
3. Hope for the best

Worse case you're gonna need to DFU that device i.e., full re-installation of iOS

hmmm unfortunately cant test it since its available jn out country

Its not battery optimization

1. It does not stop at 80%
2. Youll know it as well by the PAUSE icon; instead of the lightning bolt

image for reference https://i.imgur.com/27X5Yj2.jpg

Also OP do a restart; could be a system hangup/bug

Could be a bad charger and/or cable and/or your lightning port dirty AF

Check your date/time setting; set it to auto ; verify that the correct time zone is also selected

turn on Time zone system services setting in privacy. allow Time zone to access your location; turn it on temporarily

reboot; timezone setting table update require a reboot

Separate phones Separate apple IDs if assuming both of your phones are apple devices

If company allows apple ID registrations to non.corporate emails then grab that opportunity. Create another Apple ID/Email using non.corporate email

this is what I do

You should only be concerned if the certificate is used for decryption (as i mentioned),

But let's assume that it is; UNLESS you're using a VPN Software provided by your IT (which basically routes your traffic to them) you shouldn't be concerned about it.

A lot of managed devices enforces VPN connectivity to the company's network thus allowing inspection. We can even implement enforced VPN connectivity in which your computer CANT connect to the internet if you somehow turn off your VPN to your company ((despite your WiFi having no issues)

TL'DR;

1. if youre using mobile data with no VPN Software provided by your company - they wont be able to see your traffic
2. If youre using mobile data WITH VPN software running provided by your company - then LIKELY they are seeing your traffic; ((even without decryption; your DNS queries are quite visible so they know which websites you go to at least))

Up here! Show us the phone OP
Though looking at those pulltabs; those look really fake to me

I dont understand speak german(?)But common reasons why certificates are installed on a computer, mobile device etc. is to skip the certificate error a user encounters or allows the device to "present" itself to a network device when attempting to use it; such use cases are:

1. Decryption: They are inspecting your traffic; like the actual data(payload); many security products do this. This allows these said products to be inspect/protect you. HOWEVER, highlighting this allows your school to see your data. (this is actually a MiTM(Man in the Middle Attack) if it was not coming from a trusted source
2. Authentication: Certificate-based client authentication; could be used for RADIUS or client authentication

I'm also reading that it is unsigned? This is actually normal; these tend to be self-signed certificates (SSC). Since basically you are trusting a Root CA Certificate ((this is whole another level of discussion which I wont get into detail to)).

Considering I can see the word WLAN in there; it's likely used for Authentication i.e., allow you to connect to your schools WiFi ; could be using EAP-TLS since they are using certificates.

-Source: Working as a Systems Engineer specializing on these stuff

-Recommendation: Just take note you've installed said certificate; dont forget to delete it after like your term end there at your school. Also install it on devices you actually use for school. e.g., if you just want to connect your phone to get free internet and not use it to access school resources; then dont do it

EDIT: I am assuming your iphone is school owned, like you work at that school? If this is a personal device; tbh I would not install it, trusting a certificate is a major consideration when installing it in a personal device and is honestly a breach of your own personal privacy (especially considering your school IT likely did not tell you what its purpose is since you asked it here in this reddit)

Thanks for this!

I guess tshoot steps I would do is

1. Make sure Find My Feature is ON and location is allowed for the app with precise location enabled
2. Double check my privacy location settings; find my iphone should be enabled
3. Make sure bluetooth is ON(BLUE) or at least semi-on(Grey). Do not completely disable it in settings
4. Worse case, I would forget and re-pair my devices