Given the time of year and the presenting symptoms, this is likely anthracnose. Please see the following publications for more information, and let me know whether you have follow-up questions. Because this tree was newly planted in the fall, it will benefit from good cultural care, including not allowing lawn sprinklers to wet the foliage and providing supplemental irrigation during prolonged dry periods, equivalent to 1 inch of rain per week. All fallen leaves should be destroyed. Since the tree is not yet established, consider protective fungicide sprays next spring, as per the publications, below.

https://www.canr.msu.edu/news/maple_leaf_blister_and_anthracnose_two_foliar_diseases_that_can_appear_on_s

https://www.canr.msu.edu/news/maple_anthracnose

https://ag.umass.edu/landscape/fact-sheets/maple-anthracnose