is there a way to get the previous transaction item when processing the next Transaction item?
Yes you can by simply storing them to a different variable.
Hope this helps
Once you’ve gotten a transaction item, you’ve already gotten it. You can’t get it again. The Get Transaction activity automatically sets the queue item to In Progress, so you can’t “get” it again. Instead of using Get Transaction, you could use Get Queue Items, put them in a variable, and loop through it. Then you’d have access to the current one in the loop, the previous one, whatever you want.