Contact shadow Problem

how are you guys
I am new to unreal engine
i prepare my fine in 3dsmax and export it through datasmith and after adjusting few settings in unreal .
i am getting problem with no contact shadow i use only skylight with an HDRI .
what is the solution to get the contact shadows ??

Its working now as in preview i am not seeing any contact shadows only in production light build
as you can see there is still gap between chair and floor does there is a way to fix that and increase our shadow quality

thank you guys
thank you makigirl now shadow looks fine thank you so much for your information .