How do I sync all of my old messages from my iPhone to my Mac?

this didn't work to load any older messages from my phone to airbook.

HI Adit,

Syncing Messages from iPhone to Mac is pretty straightforward if you are using iCloud.

1. Make sure Phone and Mac is signed with same Apple ID
2. On your iPhone, go to Settings ->{Your Name} -> iCloud -> Messages.
3. Turn on the Messages Toggle
4. On your MacBook Air, open the Messages app.
5. Click on Messages -> Preferences/Settings -> Select iMessage tab.
6. Make sure that the Enable Messages in iCloud checkbox is checked.
7. Click on the Sync Now button.

Cheers

Just read and followed the steps in this reply, however after completing step 6 the Sync Now button stays disabled. I am trying to sync old text messages from my iPhone Pro Max to my new Mac mini M2 Pro. How do I enable the sync now button?