Staying Connected 2 Network

    Greetings! I have an iPhone XR & I've been having issues with it staying connected to the network 4 the past 3 months. I noticed it was after I updated to IOS 17, cuz B4 that it was working fine. I'll have a full signal then all of a sudden no signal at all! Sometimes it comes back soon but it's not stable. It goes in & out & sometimes it won't come back until an hour or 2! It's inconvenient when there's no WiFi to connect to. I've even when as far as getting eSIM cuz I was advised the SIM card might be worn out or old & needed to buy another one. Even after that I've been having same issues but it works a little better. Recently I noticed the APN # didn't show in settings so I was instructed how to add it! I'm not sure if it didn't have one or just not showing. If it didn't have one & now it does I'm hoping it'll fix connectivity issue! Now my question has to do with this iPhone having a Regional lock. The iPhone shows as SIM locked on settings under Carrier Lock but when investigating it shows as locked by US GSM/VZW N61/N56 Service Policy! All I can find out is that it's a Regional Lock & can be used with any Carrier SIM as long as it's in the U.S. So I'm wondering if it's not Carrier Locked Y would it not show as Unrestricted SIM in the Carrier Lock settings? Also that lock shows VZW when it's a T-Mobile phone & it's said that Apple made an error on some of their replacement phones & put Verizon Wireless on them? This isn't a replacement phone though. Seems that if it's only a regional lock it wouldn't be a problem using on T-Mobile but some Reps 4 the Carrier have told me it needs to be unlocked. Does anyone know 4 certain if that's true & if I got that lock off would it really make any difference?? Guy @ Apple told me that if it were locked to any Major Carrier it would show their name & Service Policy. They tested phone with 17 different tests & it passed them all! I've been told it's a Carrier issue not phone but they can only tell me it's cuz of that lock. Seems like all phones sold in the U.S. would have that lock & really only reason to unlock would be if going outside the States! I can't get anyone knowledgeable to confirm this or if it be better to unlock. I've asked UnlockBase about this & guy won't give me the info I ask. Just writes that their provider that does those kind of unlocks is offline now & they won't be able to process them until 3-4 weeks? Please advise!