To top up your Funrise wallet, go to moonpay.com
On the main page of the service there is a form for buying cryptocurrencies.
Click on the check mark in the "currency" field and scroll through the drop-down list until you find USDC - USD Coin (Polygon).
The minimum deposit amount is 2800₽
Please note that if the deposit amount is more than 22,382.95 ₽, then it will be necessary to undergo enhanced verification — KYC. You can read more about the verification here (How it works - balance replenishment)