PayPal Payments Pro is not a free PayPal account, and is not the same thing as their Business Pro account. PayPal will only allow you to use their PayPal Payments Pro account when you collect payments outside of their system.
My Account->Gateway->New Gateway->PayPal Pro->enter in your PayPal Payments Pro account email->Save
In PayPal Pro Dashboard
PLEASE NOTE:
You must have a PayPal Payments Pro account to use PayPal with Txt2Give. PayPal does not allow integrations with their free accounts. Complete the following steps in your PayPal Pro account to grant our platform permission to send donation information to PayPal to process.
Login to PayPal Payments Pro dashboard and select Profile.
Select Profile and Settings
Select My Selling Tools
Under API Acesss, click Update
Click Grant API Permissions
Add New Third Party Permissions
Enter the following email address in the Third Party Permission Username field: nathaniel_api1.spreedly.com (Spreedly is the gateway integration service that we use to connect Txt2Give to your PayPal Pro account)