group message

If you are using a Group Message that contains both iOS and non-iOS uses, then you may not see group responses from the non-iOS users. That is a fault of SMS, which is what the message becomes if there are mixed users. See this support document and the section Group SMS. Send a group text message on your iPhone, iPad, or iPod touch - Apple Support

To be honest, if your two phones are configured with exactly the same settings under Messages, I cannot say why only one of you can see the group's messages. Do you have MMS Messaging and Group Messaging turned on? If so, then I cannot provide an explanation.

My husband and I both have an XR. He can see and respond to the group message, while I can see the messages come in as individual messages. If I respond I am only responding to a single person, not the group. Our settings are the same. I've checked privacy settings as well. What do I need to do to have the same experience as him since we have the same phone?