Galaxy Note 9 DeX mode

I think you have to buy a docking station

go to your near service center

Customer care executive told that DeX mode will work only on hdmi monitors only and not on Laptops

You need to have Hdmi input port Laptops have an output Hdmi port and hence Dex mode will not work on Laptops. You need a monitor or a tv screen for it to work.

We apologize for the inconvenience caused. Regarding your concern we would suggest you to visit nearby Samsung service center in order to get your device physically inspected by the Service Engineer. Please find service center details in the link provided -http://www.samsung.com/in/support/servicelocation Be sure to hit ♡ when you find an answer that works for you.
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