Messages shoing as Group message on Apple Watch, but not on iPhone

Hi.

A friend of mine (iPhone user) has a message-group on his phone, consisting of iPhone users and Android users. When he sends out messages to this group, the message will show as a message from him directly, on my phone. If I answer, only he gets the message.

On my Apple watch, I can go into messages, find the same message, and I can see that it has been sent to 20 receivers. If I answer the message on my Apple Watch, all the people in the group gets the message.

If an Android user replies to a message, all people in the group receives the message, but for me it looks like the message comes directly from that user, and not in a group. That being on my phone. On the Watch it comes as a group message.

Can you give me a fix for this?