Border stroke not same on left and right side in custom shape

Question

I'm trying to create an arrow without bottom line but when I'm applying border stroke. left side and right side border width and color are showing up different. Any idea why this is happening or any different approach to get arrow with border and a color to fill inside the arrow

Box(
    modifier
        .fillMaxWidth()
        .height(height)
        .border(border =  BorderStroke(1.dp,borderColor), shape = DrawTriangleShape())
        .background(color = color, shape = DrawTriangleShape())
)

class DrawTriangleShape : Shape {
    override fun createOutline(size: Size, layoutDirection: LayoutDirection, density: Density): Outline {
        val trianglePath = Path().apply {
            moveTo((size.width / 2 ) - with(density) { 10.dp.toPx() }, size.height)
            lineTo((size.width / 2), 0f)
            lineTo((size.width / 2 ) + with(density) { 10.dp.toPx() }, size.height)
        }
        return Outline.Generic(path = trianglePath)
    }
}