The cost is the latest in a series of unexpected overruns in the city’s 2018 budget. Earlier this year, Allentown officials tapped reserves by $3.5 million to correct a more-than-decade-old budgeting error. Another $596,712 was taken from reserves in April to pay for remediation of a virus that struck vital city computer systems. In August, $600,000 was used from reserves when the city put extra money toward legal bills.