I need some iPad recovery tool.

Hi everyone,
I need some ipad recovery tool. My ipad was not functioning well for almost two weeks and I am worried. I bring the ipad device to a technician and he told me that he reformatted the device for it to function well. But I didn’t get some back up for my important files stored in the ipad, how can I possibly recover those files?
Thank you and have a nice day.
