Normally, the Time to Resolve field shows the total time taken by an issue from open to resolving. If any user wants total time to be calculated from different statuses to resolve, then the user should follow the below instructions.
Instructions
Create a calculated field by navigating to AIO Reports → My Area → My Calculated Fields & click Create New Field button.
Configure the calculated field as an example below. You need to mention all the intermediate status
Add the calculated field in your report to get total time to be calculated from different statuses to resolve