deleting index column but index=False not working
#### Code Sample, a copy-pastable example if possible

```python
df_new.to_excel('Misclassification.xlsx',index=False)
df.to_excel(output_file_name,index=False)

```
#### Problem description

I tried to export the dataframe into excel, and wanted to avoid the index column. However even I use index=false, it still failed. Would you able to help with it? Thanks. I'm using python 3.6 on Jupyter notebook

