Why is Google indexing the wrong link for my product?

[IanSpencerAMIT]

Hi Everyone,

I did reach out to Shopify Support, but they were pretty poor in what they suggested, in fact, they literally just Googled it themselves. 

I have had some seriously good rankings over the past year, but have seen a lot of movement up and down.

I have identified an issue as this (this is an example)

(I have removed the main web address, just in case this was not allowed.

URL CHANGES HISTORY

Nov-17 2022

https://MYEXAMPLEWEBSITE.co.uk/products/bedtime-baby-bath 

Dec-23 2022

https://MYEXAMPLEWEBSITE.co.uk/products/bedtime-baby-bath?pr_prod_strat=copurchase&pr_rec_id=21e8efadb&pr_rec_pid=6600087994545&pr_ref_pid=6600088322225&pr_seq=uniform 

When Google uses the first link for rankings, I rank well.

Then it comes back is finding this second link and its happening WAY to much.

I know it has a Canoical back to the original, but why is this happening and how can I stop these pages (the second link) being indexed.

It is so frustrating as when it uses the right link, I see a huge increase in sales, but then it finds this second link, and they drop.

Is there anything I can do ?

Ian