If you need to use products tables from the deal or lead, you need for html-table with specific structure
A html-table with a required structure can be added by drop-down menu Paste value -> Products -> Example of product table
If you have added a table with products (or copied from the other source) you should to modify it via html source and made compatible structure.
should contains only one row. It'll be copied and filled by data as source has rows.