How do I fix message sending fail issue on my iPhone 15 Pro Max?

I have searched, checked settings an can find no definitive answers. I have an issue with my messages failing to send to both iphone and android. It happens in group texts as well as individual texts. I have restarted my phone, checked for more updates, triple checked my messaging settings. Nothing seems to help. It happens on celluar data and on wifi at home. Occasionally I can get it send by retrying several times but there are times when it won't send at all.

Any advice is appreciated. Carrier is Xfinity.

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