iPhone won't connect to Mango Gl-MT300N-V2

Hi! I have the following problem and am at a loss on how to resolve.

I have a Mango Gl-MT300N-V2 router and have it setup to be a repeater for my school guest network (which has NO captive portal thankfully). I tested this at home first on my home’s guest network and it worked flawlessly. My phone was able to connect with no problem. I set up the router on the school network after scanning and finding it with no issues connecting the router to the school network. Next, I connected my two PCs and two wifi based speakers with no problem. When I try and connect my iphone, I see it pop up in the client list under the offline devices but I cannot bring it online. On the phone itself, it requests the wifi password but tells me it is incorrect even though I insert the correct password. When I set the network to be open, my phone stops requesting the passcode and giving me the error, but displays a connecting symbol but never ends up connecting.

The only things that have changed between are guest network at my home to the one at school. All other settings on the router and my iphone remain unchanged.

If anyone has any ideas on how to solve this I would be very appreciative! I have exhausted all of my base-level knowledge on this subject!

Thanks in advance