Generated grey lines but in figma they are invisible

Hi, I used this code to generate table with multiple columns and rows, where rows contain lines. Lines are grey and not hidden, but for some reason they are invisible in Figma.

What I am doing wrong that they are not showing properly?

Line generating code:

          // Generate lines
          const rowLine = figma.createLine()
            rowLine.name = 'Line ' + (j+1)
            rowLine.resize((908/countColumns),0)
      
            // Change color of lines
            const colorR = 224 / 255,
                  colorG = 224 / 255,
                  colorB = 224 / 255

            rowLine.strokes = [{type: "SOLID", color: {r: colorR, g: colorG, b: colorB}}]        

            row.appendChild(rowLine)

Whole code:

figma.showUI(__html__, {height: 250, title: "Table Generator"})

// Calls to "parent.postMessage" from within the HTML page will trigger this
// callback. The callback will be passed the "pluginMessage" property of the
// posted message.

figma.ui.onmessage = msg => {

  // One way of distinguishing between different types of messages sent from
  // your HTML page is to use an object with a "type" property like this.

  if (msg.type === 'actionGenerate') {
    
    const {countRows, countColumns} = msg.formDataObj

    // Generate main (parent) frame with custom name and properties for proper auto-layouting
    const parentFrame = figma.createFrame()
    parentFrame.name = 'Table ' + countRows + 'x' + countColumns
    parentFrame.layoutMode = "HORIZONTAL"
    parentFrame.paddingTop = 25
    parentFrame.paddingRight = 16
    parentFrame.paddingBottom = 25
    parentFrame.paddingLeft = 16
    parentFrame.primaryAxisSizingMode = "AUTO"
    parentFrame.counterAxisSizingMode = "AUTO"
    
    // Generate lines according to 'countRow', name and resize them
    for (let i = 0; i < countColumns; i++) {

      const column = figma.createFrame()
          column.name = 'Column ' + (i+1)
          column.layoutMode = "VERTICAL"
          column.primaryAxisSizingMode = "AUTO"
          column.counterAxisSizingMode = "AUTO"
      
      parentFrame.appendChild(column)

      for (let j = 0; j < countRows; j++) {

        const row = figma.createFrame()
          row.name = 'Row ' + (j+1)
          row.layoutMode = "VERTICAL"
          row.primaryAxisSizingMode = "AUTO"
          row.counterAxisSizingMode = "AUTO"

        column.appendChild(row)

          // Generate lines
          const rowLine = figma.createLine()
            rowLine.name = 'Line ' + (j+1)
            rowLine.resize((908/countColumns),0)
      
            // Change color of lines
            const colorR = 224 / 255,
                  colorG = 224 / 255,
                  colorB = 224 / 255

            rowLine.strokes = [{type: "SOLID", color: {r: colorR, g: colorG, b: colorB}}]        

            row.appendChild(rowLine)

        // Select generated table and zoomm-in
        const selectFrame : FrameNode[] = []
        selectFrame.push(parentFrame)
        figma.currentPage.selection = selectFrame
        figma.viewport.scrollAndZoomIntoView(selectFrame)
      }
    }

    figma.closePlugin('Table generated successfully :)')
  } else if (msg.type === 'actionExit') {
    
    figma.closePlugin();
  }

};

You need to add clipsContent = false when creating the column and row frames.