Increase in duplicate page titles due to canonical tag issue

[SDdigital]

Implemented canonical tag (months back) in product pages to avoid duplicate content issue. But Google picks up the URL variations and increases duplicate page title errors in Search Console.

Original URL: www.example.com/first-product-name-123456

Canonical tag:

Variation 1: www.example.com/first-product--name-123456

Canonical tag:

Variation 2: www.example.com/first-product-name-sync-123456

Canonical tag:

Kindly advice the right solution to fix the issue.

[katemorris]

Can you share actual instances? Feel free to PM me those. I need to look at the actual setup. The above looks okay, but there might be something else going on.

Also, remember that a canonical is a suggestion. If the SEs deem the page valid enough, different enough, or just plain don't know what to do with them yet, they can still index them.

Let me know the real URLs and I'll take a look.

[SDdigital]

We require "id" while generating canonical tag for the product pages. I tested with couple of online SEO tools and result seems to be fine.

[Yoav-Blustein]

Well in theory it looks good except:
Why do you use id tags in canonical code and why your code doesn't start with rel="canonical"?

Of course you can use canonical tag alongside with other tags, such as hreflang ( i use it and it works perfect but i start my "<link" with="" canonical,="" than="" hreflang="" and="" then="" the="" url="" in="" question).="" but="" still,="" to="" my="" knowledge="" you="" should="" start="" link="" statement="" a="" canonical="" tag...="" <br="">i would always start with: Have you checked in various SEO tools if they can find  that you have canonical code in your page? </link">

Maybe someone can enlighten me if i am wrong