According to a statement from ZOL the system upgrade is to improve the service delivery.
"This is part of our continued efforts to improve availability, reliability and performance of our services." The statement said.
The system upgrade is supposed to last for eight hours only and ZOL has advised those who will continue to experience connectivity problem to contact ZOL support team.
"Should you experience connectivity problems after the stated maintenance times, kindly contact our Support team on 08677 123 123 and reference your Customer ID Number," they said.
