Thank you for the information and your question. I see by the extra notes added to your original post that there is an issue with a "paycard." Although the employee can ultimately file a wage complaint with the State for not being paid, they must first exhaust their administrative options with the employer. That means contacting HR, or payroll, and trying to resolve it through them. If he is unsure how to do that, he might check all of his paperwork he signed, and got copies of, when he was hired, or ask a fellow employer or the boss of his manager (usually GM or District Manager) If they can't them they can file their wage claim.
As for how often an hourly (I assume that he is a non-exempt employee because of his age and type of business) employee in Missouri must be paid 2 times a month. The wages must be paid within sixteen (16) days of the close of each payroll period. Usually, during the initial employment period, if it starts at an odd time during the pay period, might result in only 1 paycheck in the first month because of the 16 day rule from close of payroll period. That, I can't guess about since I don't have his file in front of me. The statute that governs payroll payments is Missouri Statutes 290.080.
This is the link that he can use if he needs to file a wage complaint with the State: http://labor.mo.gov/DLS/MinimumWage/file_complaint
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