Your money is more likely on hold this is why you can't withdraw the funds , PayPal is run by crooks and scam artist, they will hold your funds as long as they can to collect interest on it, you are not alone they do this to millions of there customers
I'm facing the same problem and Upwork says it's Paypal who refuses to receive money. As far as I could find out it's because I'm from Ukraine. They say if you have Ukrainian account you can only pay with Paypal but not get paid. But so far I haven't found any confirmation of this information at Paypal. Maybe your problem is similar
I decided to leave UpWork. I feel like a good chunk of my earnings is going toupwork. 20% service they charge for their services (the website tht is constantly crashing) and poor support is beyond ridiculous.
