Based on your scenario, I take it that you've canceled your account before and you want to reactivate it now. Thus, the steps vary depending on the type of payroll subscription you previously have. I can share some steps and info to ensure you can reactivate your payroll subscription in QuickBooks Desktop (QBDT).
If you have QBDT Payroll Enhanced, Standard, or Basic payroll before, you have a couple of ways to achieve this. Before doing so, please ensure you have a supported QBDT version.
First, you can do this through your company file. Here's how:
Go to Employees at the top, and then select My Payroll Service.