Have you already tried the Looker Studio troubleshooting steps, and you've had a look at What does this Looker Studio error mean and how can I fix it? If you are still having a problem with Looker Studio then it's time to reach out to our support, we're here to help.
For us to give you the best possible help, we ask you to include 4 pieces of information:
1) A link to the Data Share
2) A screenshot from Looker Studio
If you receive an error, make sure your screenshot:
shows the error message clearly (you need to click "details" to show the whole message)
If there is a mismatch, make sure your screenshot:
shows data for a single day. Not today or yesterday as recent data might take a few days to stabilize in the Data Source
shows the same dimensions that you're comparing with in Funnel
contains the entire browser window, including URL and any date range and filters
3) If there is a mismatch; a link to the Data Explorer in Funnel
Make sure the Data Explorer view you're linking to is showing the same data as you're comparing it with in the Data Source platform:
the same date range
the same dimensions
the same metrics
the same currency conversion
no filters applied
4) Any additional relevant context
Please include any other relevant context. For example; what were you trying to do when you ran into the problem? Has this happened before?