Wrong calculations

I am still having problems with calculations, I have added to cart total weight of 2.6 kg, but plugin is not calculating it. I am on latest version of plugin and WP.

Debug

Peso total: 1
Volumen: 0
Largo: 0
Ancho: 0
Alto: 0
Medidas: Array
(
    [0] => Array
        (
            [largo] => 
            [ancho] => 
            [alto] => 
            [cantidad] => 1
        )

    [1] => Array
        (
            [largo] => 
            [ancho] => 
            [alto] => 
            [cantidad] => 1
        )

    [2] => Array
        (
            [largo] => 
            [ancho] => 
            [alto] => 
            [cantidad] => 1
        )

)

Clases: Array
(
    [todas] => 1
    [sin-clase] => 1
)
Tarifas: Array
(
    [sin-clase] => Array
        (
            [0] => Array
                (
                    [peso] => 2
                    [importe] => 28.73
                )

            [1] => Array
                (
                    [peso] => 3
                    [importe] => 34.93
                )

            [2] => Array
                (
                    [peso] => 5
                    [importe] => 36.35
                )

            [3] => Array
                (
                    [peso] => 10
                    [importe] => 39.65
                )

            [4] => Array
                (
                    [peso] => 15
                    [importe] => 44.36
                )

            [5] => Array
                (
                    [peso] => 20
                    [importe] => 49.06
                )

            [6] => Array
                (
                    [peso] => 25
                    [importe] => 53.78
                )

            [7] => Array
                (
                    [peso] => 30
                    [importe] => 58.50
                )

            [8] => Array
                (
                    [peso] => 40
                    [importe] => 70.28
                )

        )

)