How to use linq group with count and return ToListAsync to front end

This is my code. I need to use linq group and count after return to front end by ToListAsync.
But I got a error like this picture
How can I fix it?

    public async Task<List<Product>> GetDataChart()
    {
        var data = await dbMLIMPORT.Product
                    .GroupBy(g => new { g.CMID, g.SUB_CODE })
                    .Select(s => new
                    {
                        CMID = s.Key.CMID,
                        SUB_CODE = s.Key.SUB_CODE,
                        COUNT = s.Sum(x => x.PRODUCT_ID.Length > 0 ? 1 : 0)
                    }).ToListAsync();
        return data;
    }

Answers:

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Method 1

You need to create a new class ProductInfo and return a list of ProductInfos instead of a list of Products. Currently, you are creating anonymous type inside the select query and returning the same which will produce this error.
I hope, it will solve your problem.

public class ProductInfo
{
    public string CMID {get; set;}
    public string SUB_CODE {get; set;}
    public int COUNT {get; set;}
}

public async Task<List<ProductInfo>> GetDataChart()
{
    var data = await dbMLIMPORT.Product
                .GroupBy(g => new { g.CMID, g.SUB_CODE })
                .Select(s => new ProductInfo
                {
                    CMID = s.Key.CMID,
                    SUB_CODE = s.Key.SUB_CODE,
                    COUNT = s.Sum(x => x.PRODUCT_ID.Length > 0 ? 1 : 0)
                }).ToListAsync();
    return data;
}

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