Based on the information provided in the context, if you are unable to pass the system checkup during your PL300 certification exam, and the reschedule option is not available due to routine maintenance, you should contact Pearson VUE support to resolve the issue. You can reschedule or cancel existing exams appointments through the certification dashboard or by contacting Pearson VUE Support. Please note that currently customer service wait-times are longer than usual.
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