Purge/Delete Dats for a Year

Hi. My Company was sold at the end of 2020 in an asset sale. The acquiring Company continued to use the QuickBooks Online version in 2021 that I had used from 2008 to 2020. 

The new Company has since moved off my QBO version and I need to go in and purge all transactional data input by the new Company in 2021. Is there an easy way to do this?  Thank you!