Unfortunately, you may not be able to get it. You can try to call the Boston office, but, they do not always check the bus so it is a chance that someone from the next group of passengers may have taken it. Wishing you luck on retrieving your belongings.
Go to the NY station and give your information to the station staff. They will need to know what day and time you board the bus and where you left your item. If your things were found when the bus was being cleaned, they will be secured and brought to the lost and found. Be sure to have your information when you go to the station.
You should call them. This page is run by Google, with questions from Google users answered by other Google users. It's not a Lucky Star page.
I believe you can call them tell them the time and item lost perhaps they might have left it in there office could try.
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