imessages will not sync with my macbook

Messages > preferences > Accounts

You can be reached for messages at:

by telephone number, by apple-id, by other email and/or by multiple additional email addresses.

To get uniform results, you must have the SAME entries in each version of messages (iPhone and Mac).

This may help, I did a search and it worked for me:

how-to-fix-iphone-messages-not-syncing-with-mac.htm