Thanks for your response. Exterior surrounding was mulch of about 1 feet from the wall. Will check with construction company about grading. Will home insurance cover this?

Okay. Any suggestion please, on what should be my approach to solve the problem?

It does appear that the exterior soil is higher than the slab. That will always allow water into the interior. The grade away from the home should start 6" below the sill plate, and extend away from the home 10 feet or more. If you closed during winter weather, where final grading was yet to be done, that could be one explanation for improper grading. But this is a builder issue, and should start with him, and his warranty for his work. If you are unable to get a satisfactory solution after those conversations, then pictures and measurements are useful tools when visiting your code inspection office. If you do not have a laser level to shoot the horizontal line, you can use a water level. It is simple and inexpensive to build. But, I would highly recommend buying a 3 axis laser level for general home use. It's great for hanging pictures, and all kinds of home projects.

Thanks for taking time to explain. Will buy axis laser level and check grading

You need to contact the GC, or better, the general liability insurance company listed on the insurance certificate you obtained from the company.