Online multiplayer not working - boo – Conquist 2 Review

Enjoyed playing multiplayer with my family on the same phone this weekend. Bought this app to play with my brother on our different cell phones when we’re not hanging out. But online multiplayer is said to not work in my device - an iPhone 8 Plus. How can this be? Tried using app support to resolve but it was a confusing dead end. Please resolve ASAP or refund my purchase.
Review by Humphrey Jones on Conquist 2.