Why can't I restore my contacts even after I synced them to my Google account?

[AC Question]

why can't i restore my contacts even after i synced them to my Google account

i synced all my datas specially contacts to my Google account. after i reset my Galaxy S3 and tried to restore my synced data, it keeps saying i did not backed any data to Google account. is there any way i can get my contacts back after i restart my phone, because it also keeps saying "If you do not restore your account before backing up your data, all data previously backed up to the server will be deleted". please help