People are being urged to avoid calling the Digital Covid Certificate helpline unless their queries are urgent or they are traveling in the next ten days.
Fewer than 3,000 out of 40,000 calls to the helpline over the past two days were dealt with. Liz Canavan, a senior official at the Department of the Taoiseach, said there are "long waiting times for many callers and the centre has not been able to meet the level of demand".
Addressing the Oireachtas Committee on Health, Ms Canavan said many people who are calling are not due to travel in the short term and "these non-urgent calls are adding very significant waiting times to all calls, and preventing many urgent calls from getting through".