Q: Ios 9.3 is already available on my ipad. What happen is that I accidentally delete it. I tried using itunes for latest updates but its not available. My device is up to date 9.2.1. But the latest version is available on my device. What will i do?

THe latest version of ios 9.3 is already available on my ipad 2. What i did is that I accidentally delete it from my device at the storage & icloud usage. Then i tried connecting it to itunes to recover the ios update. but it is not available. How can i recover the ios 9.3 from deleting it from my device? Please help me..