iPhone 17 pro Cellular Connection Issue

Update : I found the issue ! This was related to VPN.LAT software !! this vpn application, even if the vpn was disabled in the iphone settings, crash and reboot my e-sim(s) !

Once uninstalled, everything works fine

Should be fixed in iOS... probably

I had issue with my new iPhone 17 Pro. It could not hold even one minute long conversation over FaceTime or WhatsApp or any data call. I did a lot of research, I went to the Apple Store and they ran the diagnostics. Everything comes fine. What finally did the trick was to delete all my eSIM and reinstall the eSIM by going to my T-Mobile store. The problem that is happening is the eSIM gets transferred to the new phone and that’s where there are some challenges. I guess the work around towards this is only to delete your eSIM and then reinstall mind you in the network store. They might just refresh the eSIM, but that does not work, you have to delete the eSIM and then reinstall the eSIM by the carrier.

I changed 5G to LTE and the issue went away. Definitely an Apple issue.

I had same problem. Have u tried to have a technician at Verizon reset your SIM card through your settings ? This resolved my issues

Different community members are having different user experiences. I think it’s fair to say some members are having what you’re calling software/firmware issues. However, throughout several threads on this issue members report having their eSIM reprovisioned and resolving the issue.

The first determining factor will be which manufacturer supplied the baseband modem. Qualcomm plays a major role in firmware for their baseband chips. The new C1 modem made by Apple would be solely the responsibility of Apple.

If the bug is in a proprietary Qualcomm subsystem or a proprietary modem firmware layer, Qualcomm must first provide a corrected firmware update to Apple, which Apple then integrates into its iOS based modem update that’s delivered with the iOS update or via a DFU reset.

Would you agree?

there is a new software update 26.0.1 try and see if it’s fixed 🙏🏾

I keep it on LTE and it's good. It's a shame this hasn't been resolved yet. The issue is it can't go between 5g and LTE. Updating the OS does nothing

Are you using a VPN? It’s a known issue that can cause what you’re experiencing. Do you have any profiles in,

iPhone > Settings > General > VPN & Device Management > ??

I have the same connectivity issue since the IPhone 14pro. The phone keeps dtoping calls within a few seconds of the conversation! Several

times a days at any time I may have to call the person back 5-6-7 times to get a stable connection. Another issue is when I call out, it says “call failed” and I have to try 7-8 times to finally get it through. A third problem is people call me and the phone doesn’t ring, it goes straight to voicemail. I checked with my carrier ATT and they checked everything, there is no issue on their end. Also I have 2 other older iPhones on the same ATT service: those phones have no issues. So it is not a carrier issue. I brought the phone to the Apple Store to get it diagnosed a couple of times and no hardware issues.

the call drop is definitely an Apple software issue…

i was so frustrated because I use the phone almost exclusively for work.

thos last week I went to get an iPhone 17 pro, hoping to get rid of this problem.

but the 17pro has exactly the same problem!!! I give up.

if someone has a solution please post it here! I don’t know what else to do…

Came across this while researching calling issue on iPhone 17 pro for my boss. Apparently he can’t seem to make calls randomly. Incoming calls work fine but can’t seems to make out bound calls to centain mobile numbers. I’ll try to reconnect the device to the network or remove eSIM and install if still doesn’t work. The slow and connection issue can be related to private relay in iCloud. Try turning that off to see if it help. Spees test is serval time faster after turning that off. Turn of only if you need to mask your traffic.

First recommendation is to update to iOS 26.3 released just last week. It contains, among many things, bug fixes and optimizations.

Update iOS on iPhone - Apple Support

If that doesn’t resolve the potential issue, contact your cellular service provider and ask them to verify operation of SMS text on your account/line. In my experience the vast majority of texting issues are carrier related.

Nothing. No solution to fix. I just turned on LTE. Then I don't have the issue. Terrible I can't use 5g

its definitely a firmware or software issue after updating, I had the same issue and just got a new Esim instead.

I’m having the exact same issue and it’s incredibly frustrating. Ever since I upgraded to the iPhone 17 Pro Max (about a month ago), I’ve been experiencing constant signal drops. Both of my eSIMs — one from AT&T and one from Telcel (MX) — lose signal randomly, and the only way to get it back is by restarting the phone. It even disconnects from Wi-Fi at home.

I never had this problem with my iPhone 15 Pro Max. That phone was rock solid. This one? Not reliable at all.

I’ve taken it to the Apple Store three times. They ran diagnostics twice and found nothing. They just keep pointing me back to AT&T. AT&T, of course, says everything looks fine on their end and blames Apple. It’s a never-ending loop of finger-pointing.

On my third visit (today, November 5), I insisted they send the phone in for repair. They agreed — but only to replace the logic board, as if they still don’t believe there’s a real issue. I’ve had AppleCare for years, and yet they refuse to replace the phone outright.

I deeply regret upgrading. This phone has been nothing but problems, and no one wants to take responsibility. Something is clearly wrong — and I know I’m not the only one.

This link provides some info on why these connectivity issues are happening & steps to try to fix them.

https://mobilityarena.com/cellular-connectivity-issues-on-iphone-17/

I haven’t tried any of the suggestions yet, but maybe some of the ideas will be helpful.