phone won't ring calls go straight to voice mail

I am having the same problem! Only certain people were able to call through. I missed so many calls! I had random voicemails with no missed calls. Call forwarding is not on, I have service. Not sure what the issue is but this is the first time in about a year that I had T-Mobile that I had this issue. I'm quite annoyed.

and I have an iPhone. You'd think that would matter even FaceTime don't work sometimes!

My parents experienced this issue recently, and it turned out that they had accidentally blocked me. So anyone else could call/text them, but if I did, it would go straight to voice mail. Because they almost never receive calls on their cell phone from anyone, none of us realized that it was an issue specific to me rather than a general "not receiving calls" issue.

For iPhone, you can see the list of contacts/numbers that are blocked via Settings → Phone → Blocked Contacts and then add/remove entries as desired. Alternatively, if you're seeing an issue with a particular contact, go to their entry in your Contacts list and at the very bottom of the details there will be a link to "Block this Caller" (indicating that the contact is currently not blocked) or "Unblock this caller" (indicating that the contact is currently blocked).

@Xxcolleenxx91 , this might be your issue, too.

I've been plagued by the same problem for months since I switched to T-Mobile.    Customer service has been totally not helpful.  When it happens I've received a text that the call has gone directly to voice mail from my contact.  They try again and this time it goes thru.  It's very inconsistant.   Has to be a T-Mobile tower issue.  Not enough bandwith for all the activity.  Strange that this has been going on for years with no resolution.  I will be leaving T-Mobile shortly.  Cheapest is not always the best!

Just to share with you, it may help. On Pixel 6a, you set

Settings > Network & Internet > SIMS > Preferred Network Type > 5G (recommended)

and scroll to the end in [Access Point Names] check both

[Allow 2G] and [Vo5G]

I guess your voice is going through Vo5G now but you did not enable it, your phone still uses 2G, 3G and 4G/VoLTE for voice. I don't see anyone would like to limit your phone to 2G, 3G or 4G networks because of voice call. In stead, you should enable Vo5G and use 5G networks.