Can't share internet connection from iPhone to AR750

I have an issue when using wireless sharing on my iPhone with the router, I have unlimited data and want to share it with the AR750 (Creta) which would handle all the networking staff (all my other devices would connect to it instead of my iPhone), unfortunately it’s not working reliably at all, the router keeps disconnecting from the iPhone, it just unusable.
I’ve an android phone that I tried and it works just fine, it driving me nuts, any help would be greatly appreciated.

Have you considered the usb-tether option. I have the 750s with default release 3.104 firmware and iPhone 7 it’s been working well.

Honestly no, the router is in another room and I use my phone for basically everything from reading to watching YouTube and tether the phone physically isn’t the best option for me.
I might try it though to see how it’s working.
I’m on the same firmware BTW 3.104

If you have unlimited data in your phone and you use it heavily, then it is better that you put the unlimited SIM in the router (consider our 4G router Mudi) instead of your phone so that your data can be shared.

But if you use the SIM card for calls etc. then you have to use on your phone. This is exactly what the carrier wanted you to do.

That’s exactly it, I use my phone for calls a lot, I can’t put my phone away since I need it for calls or messages or emails, put the SIM in the router or 4G modem for that matter isn’t an option either.
I bought this router in the first place because the iPhone has a max of 5 connected devices at a time which is very handicapping, I have a lot of devices that need to be connected to the internet and I don’t have any internet access apart from my phone.
I’m really disappointed of the router and now I’m considering another brand/model that could serve that purpose if anyone have a suggestion

Same problem here. I’m activating the hotspot on the iPhone and connecting to it through the admin panel in the Repeater section. I have also tried to use the openwrt luci thing to connect to it.
The connection takes quite long to establish (order of 20-30 seconds) and then drops within 5-10 minutes and the hotspot is disabled. On the iPhone, the hotspot is disabled automatically after some time without any new connections.

On the other hand, connecting a Windows laptop to the iPhone hotspot and then activating the hotspot on the laptop and only then connecting the AR750 to the laptop, effectively routing iPhone internet through the laptop first before connecting it to the AR750, results in a stable connection that does not drop.

iPhone → AR750 = unstable
iPhone → laptop → AR750 = stable

So perhaps there is some TTL or some other setting in the openwrt which can be modified to keep the connection with the iPhone.