By Pat Warren

BALTIMORE (WJZ)–Maryland state workers are finding out they may not have been paid what they’re due.

State officials say extra pay for overtime and night shifts has been miscalculated for years.

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The state notified public-employee unions on Friday that there’s been a problem with calculating extra pay.

“It could affect not only they thought about 13,000 folks, but you go beyond that to people who have worked for the state for years and left,” said Patrick Moran, President with American Federation of State, County and Municipal Employees (AFSCME).

A Department of Budget and Management spokesman tells WJZ this payroll issue predates the Hogan administration, but we discovered the problem and we are committed to fixing it.

It estimates up to 13,000 current employees affected, each could be owed from $2 to $30 a pay period.

Moran says discrepancies had been reported.

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“I think some employees noticed things and they brought it up in the past and it was dealt with and they would mark that as, ‘oh, that’s a glitch or a one-time problem.”

In addition to AFSCME, health and law enforcement employees are also affected.

Moran says the process could take awhile.

Budget and Management met with unions today saying in a statement, “we met with representatives from various employee unions today and will continue to work closely with them on a plan to make it right.”

“We expect nothing less than them following the law,” says Moran.

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State Budget Secretary David Brinkley was not available to answer questions today.