Convert an excel xlsx file with nested headers into json

I am converting my excel file to json using the below library and it works fine when I have one header row and the remaining rows are data.

var excelToJson = require('convert-excel-to-json');

var result = excelToJson({
sourceFile: 'Auto.xlsx',
header: {
    rows: 2 //Used 2 to skip the first line of headers
},
columnToKey: {
   '*': '{{columnHeader}}'
}
}); 

But I have a file that has nested rows as headers similar to below and want to convert that into json.

Something like this, with multiple sheets

Appreciate any help or pointers. Thanks!