Your account could be limited, one of the most severest annoyances of the PayPal service. You will often see a red alert in the bell on the top right side of the screen, if one has been placed. This will redirect to the section which outlines the many documents PayPal seek to review.
You can also check for a limitation via the Resolution Center. If nothing shows, it could be a temporary internal security block on your account, another frequent annoyance intended to stop fraudsters, although seems to have a frequent habit of stopping genuine account holders from using their cash as well.
If all fails, contact PayPal by telephone to quickly address any problem. There is not much in regards to troubleshooting a blocked service and I'd rather not waste your time with it.
