I had the same problem. After rendering, some objects had shadows, while my car model didn’t have any.
I got it resolved.
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Simulate your viewport(Alt + S) to check for errors. The error I had was “Out of memory for skin cache, requires 380.00 extra mb”
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Go to project settings —> maximum memory to compute skin cache. I increased mine from 128 to 400 MB.
After rendering it again, the car shadow came out perfectly.