erratic service meaning in English

班次欠准

The increase was mainly attributable to more complaints about passenger services and facilities and erratic services
个案数目上升的主要原因，是有关乘客服务及设施和班次欠准的投诉有所增加。
The number of complaintssuggestions on the east rail increased from 29 in 2002 to 50 in 2003 . this was mostly due to an increase in the complaints about passenger services and facilities ( particularly inadequate announcements during service disruptions ) and erratic service
有关东铁的投诉建议由二二年的29宗上升至二三年的50宗，主要原因是涉及乘客服务及设施（尤其是在服务受阻时向公众发布的资料不足）和班次欠准的投诉有所增加。