If you are trying to delete a paired intercompany transaction then we won’t be able to delete the record
Error:

For deleting the Records
1).Open paired Purchase order> Edit
Change the item into a Non inventory item>
Save the transaction record
2).Open paired Sales order record> Edit
Change the item into a Non inventory item>
Save the transaction record
3). Edit the purchase order record
now the paired transaction field will be editable
delete the data from the field paired intercompany transaction
save the record
4).
3). Edit the sales order record
now the paired transaction field will be editable
delete the data from the field paired intercompany transaction
save the record
Edit the purchase order record
click on actions > Delete
Edit the Sales order record
click on actions > Delete