Cannot Remove / Downgrade from Full Domain Privacy and Protection on Renewal

I tried to remove my website's protection (Full Domain Privacy and Protection - Renewal) to reduce upfront renewal payment... but I cannot delete that option in my Shopping Cart.

I tried to downgrade the protection but it says "You already have the lowest level of security on your selected domains."

I am aware of the consequences of removing the privacy protection. I plan to renew it sometime soon, but for now the only important thing (budget-wise) is to renew the domain name.