Have not had this problem.
If you are using iCloud, you can get restore a backup. Sign into iCloud.com. Then go into Settings. At the lower left will be an option of "Restore Contacts". Click that. You will get a list of backups. Click the "Restore" link next to the backup you wish to use.
If you are trying to access iCloud.com from iOS Safari, you will need to press-hold the semi-circle arrow refresh button in the address box to get the "Request Desktop Site" in order to sign into iCloud from mobile. From a PC/Mac, just go to the website and sign-in.