If you use WordPressYoast or Rank Math generate these tags themselves. Don't add the code by hand or the tags will appear twice; enter the details in the plugin's fields instead.
WhatsApp cacheIf you changed the image, WhatsApp may keep showing the old card for a while. Try sharing with ?v=2 added to the end of the URL.
Why does canonical matter?If the same page opens at more than one address (?ref=, upper/lower case), it tells Google which address is the main one.