PS+ member and down for me today too. I reckon I'm just glad to know it isn't just me.
"I do not shoot with my hand; he who shoots with his hand has forgotten the face of his father. I shoot with my mind."
I do not kill with my gun; he who kills with his gun has forgotten the face of his father. I kill with my heart." - The Last Gunslinger
My playstation showed that I still had $10 in my wallet but I couldn't buy anything... Error code 80023102.
FIXED by logging into PSN Account Management from this link: https://store.playstation.com/login.gvm
Then "Edit Billing Information" to checked my Credit Card details. They had expired and actually I only had $1 in my account.
Fixed the credit card details and then topped up my Wallet "Add Funds: Credit Card" and all worked fine again.