"Your alert took down internet connectivity, but to contact you about this we need to do so through the internet...! Please fix. No internet in Hastings," one customer complained.
A Vodafone spokesperson replied to customers saying their tech teams were looking into the matter.
Shortly after 9pm, Vodafone CEO Jason Paris said on Twitter the fault had been fixed.
Earlier in the day, Vodafone had posted on its page alerting to customers issues with broadband, landline or mobile coverage: "The health of our customers and our employees is of the highest importance to us, so we are following all recommended preventative quarantine procedures.
"Because of this, a number of our team members are not available today, meaning at the moment we are only able to respond to calls regarding service restoration or queries related to medical or emergency situations.
"Rest assured our networks are still operating as normal even if our call centres are not."