You can enable the Reinvest function in the App in the Dashboard. Select  the cryptocurrency, click "Reinvest" and select how many you want reinvest to Tokens. 

This function will use your current Balance to purchase the maximum possible amount of Tokens.  

After that, the system will check if your Balance is sufficient to purchase at least a minimum amount of Tokens. If it is, then the purchase will be created and automatically confirmed.

NB!  Please note that the reinvest function is disabled by default. Coinface technical support can not restore the balance if you have mistakenly activated the reinvest.