Hey @ashishkapur
If you are confident you have set up the lookup column pointing to the contact table. Then the simple solution is
as per @EmadBeshai screenshot, set up the table permissions and make sure you add the "Authenticated" user's web role too.
More details here
once done.
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In Design Studio
1. Press the sync configuration and preview the website. Press "Ctrl+F5"
Hope it helps.
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