Macro to fill blanks with listed data

Hi,

i have a workbook with two sheets.
The main sheet is called 'app' and the secondary sheet is called' main products'

the app sheet contains products and their types and when the product changes there is a blank row. In this blank row i need to insert the row from the 'main products' sheet.

For example:
The first blank on the app sheet will need to have the information from the first row on the main products sheet. Followed by the second blank needing information from the second row.

The blank rows occur on a irregular basis, it is worth noting.


This could possibly done with a formula but i'm not sure how
I have tried using a column to create a vlookup to bring the product name onto the app sheet. Then in the cell i have used an if formula to bring across the right piece of data. However this formula cannot be simply dragged down as the cells do not correlate

These are the formulas i am currently using but if there is a way of doing this without having to type the formula manually on each one then can you let me know?

=VLOOKUP(B33835,'Main Products'!B:B,1,FALSE)
=IF(B33868=M33867,'Main Products'!A1137:G1137,0)

Thanks
Jack