There are two main ways to top up in UniFans, Regular Top-up and Quick Top-up.
Regular Top-up
Click on the top right corner of the Buy Coins center, select your top-up method, check the price details, make payment, and your coins balance should be updated shortly thereafter.
Quick Top-up
When you decide to subscribe to a sponsorship plan of a creator while browsing his/her homepage, if your balance is not enough to pay for one month's plan, you can do a quick top-up. The minimal quick top-up amount should be equal to one month of the plan's price.
Once you have topped up your account, you can proceed with your subscription.