Give us more information. How are you trying to add funds? Were you able to before?Are you getting an error code? Have you searched the forums for other people having a similar problem and what solutions worked for them?
I have had the same problem this morning. The store was down for about an hour and a half. I shut down the PS3 and restarted. I reopened the store and everything loaded. I tried to purchase Journey and "confirm purchase" (adding the five dollar minimum to my wallet to purchase the game at the PS Plus price). A message pops up that says "An Error Has Occured." There is no error number along with the message. I have tried continually and nothing has worked so far. Any recommendations would be appreciated...
Our support page has a notice about ongoing maintenence which is a possible culprit:
"In order to continue to deliver you the best online games experience, we will be performing maintenance to upgrade the software for the PlayStation Store on Thursday, August 29. This maintenance will occur between:
- Start at approximately: Thursday, August 29, 2:20PM PT (3:20PM MT / 4:20PM CT / 5:20PM ET)
- End at approximately: Thursday, August 29, 3:50 PM PT (4:50PM MT / 5:50PM CT / 6:50PM ET)
During this maintenance period, you may receive a message that states “Sony Entertainment Network is undergoing maintenance” when attempting to access the PlayStation Store or PlayStation Home."
If you are still having issues after the maintenence period, you should refer to the suggestions here:
Common credit card issues on the PSN