Apple Watch Series 3 and Iphone 8 Walkie Talkie not sending or receiving invitation

Hi meysue,

Welcome to the Apple Community.

Seems Walkie-Talkie is not available in all regions

The "Related Article" above your question gives quite a lot of info.

Yet you might try this article. too, for tips that may help:

Use Walkie-Talkie on Apple Watch – Apple Support

Eg: you may have accidentally made yourself "unavailable"

or

your friend may not have made themselves "available"

If you still need help:

There are some good trouble-shooting tips in this discussion thread

walkie talkie - Apple Community

or

Apple Watch support

Apple Watch - Official Apple Support

All the best :-)

Thank you for your reply, and for letting others know what worked for you.

Glad to know you fixed it ok, and how

All the best :-).