PayPal offers seller support against disputes from customers in certain circumstances where seller requirements are met such as valid tracking information, having an accurate product description, etc.
Customers with order issues are encouraged to first contact the shop to try to come to a resolution but if the shop doesn't respond to the customer within 2 business days or they cannot come to an agreeable resolution the customer can escalate the issue with PayPal customer support.
You will be notified of any created disputes and will be able to find these on your PayPal dashboard in order to provide your details to the case. You can find out more information on the PayPal Seller Protection policies here: https://www.paypal.com/us/security/seller-protection