Intermittent Incoming Calls Going Straight to Voicemail with No Ring

I have been having the same issue, T-Mobile won't resolve. I have a Samsung S10 and my son has a Motorola, and we have the same issues. They have told me it is my phone or my house (must have suddenly been encapsulated in lead without me knowing) but not a T-Mobile issue. Funny, same issue on two different types of phones! Looking for a new carrier after 7 years. T-Mobile is the worst for customer service. Very disappointing. One tech tried to sell me a new Samsung, another offered one for free, and the third offered me a phone for a price...entire team in Idaho. Not very honest or consistent in their replies, other than "It is not a T-Mobile issue". 

I found a solution to the straight to voicemail problem.

Delete T-mobile visual voicemail.

Not surprised that the problem originated with t-mobile, not the phone.

So I am using oneplus phone and encountered same question recently(I cannot received any phone calls and they all went to voicemail without ring).

Here are steps I tried:

1. I called 611 and a representive told me to try deleting all the unimportant voicemail. After I deleted all my voicemail,  the problem disappered, but after a few hours, it showed up again.
2. I followed the official instruction and dial ##004# to reset some settings(##21# does not worked for me), and followed solution in this post, dial **61*18056377243**30# to set ring time to 30s(someone mentioned ##40# but that does not worked for me as well).
3. At last I updated my Coloros system and found out that signal icon changed to 5G and there is an HD icon as well, then everything works well for me. 

Personally I think this problem is related to 5G, volte, Android/OS version and voicemail. I think update the system solved the problem but not sure whether step 1 and 2 played some role in solving this problem. So I wrote these steps down and hope it will be helpful for someone.

It doesn't seem to be an issue with the carrier or phone. I had this problem from time to time with my previous two carriers. I think it has more to do with towers/reception than the phone or carrier.

I am having the same issue for all my phones for over a month it seems, incoming calls thru whatsapp work, but regular phone calls work inrtermittently, mostly does not work! Yet to find a solution for the issue, may be forced to change carrier if issue continues.
 

Same problem here too. 

Having same issue. Was told by friends to dump T-Mobile. Once dumped, no issue with other carriers.

This might not work for everyone, but what worked for me was turning off Wi-Fi Calling (Settings > Network & Internet > SIMs > T-Mobile > Wi-Fi calling off). I have a Google Pixel 6a, and people were complaining that they had to call me 2 or 3 times before my phone would actually ring. The first 2 calls would go straight to voicemail, and I did not receive a missed call notification on my phone. Somehow I think that the phone just misses the call as it's trying to decide whether to route the call over WiFi or the T-Mobile network.

I'm having this issue as well.  I've done all the steps, swapped my device, installed a new sim, and even standing in the store had the associate try to call me and no call came through.  I am absolutely fed up with the issue and lack of resolution. I've been a sprint customer for years and never had this type of problem.

This isn't a device or location related issue as it persisted across the whole state of Texas during a business trip.  Figure this out T-mobile, its ridiculous that for 2 months now you've wanted payment (that I paid on time, everytime) for a service that does not work.

tmo_mike_c wrote:

Issues like this are mainly need Solución de problemas de señal to get this resolved. I'd start there first and follow those common steps to fix this.

This is not true I know for a fact it's the network I've been having this problem for at least a few months that I know of T-Mobile said it was not their network. I just got my new iPhone set up today that I had to warranty out through the iPhone store, and I have the exact same problems. My brother is actually here right now calling me Numerous times in a row standing right next to me and calls only go through sometimes at least six or seven calls went straight to voicemail in a row then 20 minutes later, same thing it's T-Mobile. I've talked to them numerous times went to the stores replace the Sim cards. All my settings are turned off for call blocking or silencing unknown callers. I've got a brand new iPhone, which there was nothing wrong with the other one I had, and  The only option is to leave T-Mobile and go back to some other carrier, which is unfortunate because I like T-Mobile service and I'm OK with my plan, but if I'm not getting my calls, it's crushing my business and my emergency calls, especially with my special-needs son