We have been using Tableau with Big Query connector on our licenced version 10.2.
But since few days we are not finding the Big Query connector on Tableau and hence not able to import the data from Big Query for our dashboard.

We have been using Tableau with Big Query connector on our licenced version 10.2.
But since few days we are not finding the Big Query connector on Tableau and hence not able to import the data from Big Query for our dashboard.

It looks like you are running Tableau Public or Tableau Desktop Personal edition.
You need Tableau Desktop Professional to connect to BigQuery. See: https://www.tableau.com/products/techspecs
If you have Public/Personal and Professional installed make sure that you are running the correct program (it can be confusing since they have very similar icons).
You can easily double check what program you are running by going to:
help -> "About Tableau" and checking to make sure that you see: