How do I get data annotation from generic?

I have a defined generic type and custom data annotations. I want to get data annotations of this.

GetCustomAttributes not working because it's a generic type.

  public List<ColumnFilter> SetColumnFilters()
            {
                ColumnFilter columnFilter;
                List<ColumnFilter> columnFilters = new List<ColumnFilter>();


                foreach (var prop in typeof(T).GetProperties())
                {
                    columnFilter = new ColumnFilter();
                    columnFilter.Field = prop.Name;
                    Type type = prop.GetType();


                    if (type is Enum)
                    {
                        columnFilter.FieldType = ColumnFilterType.DropDown;

                    }
                    else if (type is DateTime)
                    {
                        columnFilter.FieldType = ColumnFilterType.DatePicker;
                    }
                    else
                    {
                        columnFilter.FieldType = ColumnFilterType.Input;
                    }

                    columnFilters.Add(columnFilter);
                }


                return columnFilters;
            }