Error when applying free 100GB google drive

I bought a new tablet ASUS Xen Pad 3 8.0 whose code is Z581KL. This is attached a right to expand google drive 100GB for 2 years. But I could not redeem it. Even if this is a first time to redeem it.

In my research, there are several points to redeem it.

• Google Play Service should be latest version
• Google Drive should be latest version
• Clear Google Play Service cache and restart Google Drive

I am happy if there are something to help you.