this is what it says in a pink box at the top of my account
As part of our ongoing effort to make PayPal an even safer place for you and your customers to do business, we are going to place a Payment Hold on your daily sales.
We’re committed to providing you and your customers with the fastest, safest payment service on the planet. To help protect our customers in case something goes wrong, we may set aside payments for some sellers in a pending balance for up to 21 days. This gives us time to check that there are no problems with the transaction.