Transport for NSW has confirmed that its online recharge service for Opal tap-and-go public transport smart cards is currently unavailable.
Earlier this afternoon the transport authority used its official Twitter account to warn travellers to use alternative methods to top up their travel cards.
It’s not currently possible to top up at https://t.co/oSggS6yv4N. This hasn’t affected travel with your Opal card. We’ll keep you updated.— Transport for NSW (@TransportforNSW) January 13, 2016
Some social media users reported attempting to use the recharge service but found that funds had been debited from their accounts but not transferred to the balance on their Opal cards.
A spokeswoman for Transport NSW told iTnews that the authority took the web site offline to "address a processing issue".
"As a result, top ups made at Opal.com.au are currently experiencing delays," she said.
"Transport for NSW is working to address this issue as quickly as possible."
The online outage means that Opal users with a low balance (and no automatic top-up enabled) will need to physically visit a participating retail outlet or one of 94 Opal top-up machines in order to recharge until the website is fixed.
Transport NSW gave assurances that no customer information had been compromised during the outage.
The status of phone services remains unknown.