Google uses different meta tiles from the source code

Hello I have problem with the website mybtwconsulting.com

In many pages Google is showing meta titles different from my settings and from the source code.

My website offers consulting service for merchants who want to sell on eBay and Amazon.

Google is appending the word eBay consultant to many Amazon page and it doesn't make sense to me:

Any idea about the reason?

Thanks

you have WP or HTML ?