"很高兴和你聊天" can be translated into English as:
* "I'm really glad/happy to chat with you."
* "It's been a pleasure chatting with you." (This implies the chat has already taken place and was enjoyable.)
* "I've enjoyed chatting with you." (Also implies the chat has occurred and was pleasant.)
The first translation, "I'm really glad/happy to chat with you," is more immediate and can be used either before or during the chat. The other two translations are more suitable for expressing enjoyment after the chat has concluded. Choose the one that best fits the context and your intention.