I had this happen. Two quarters. Im guessing they fell in front of the door/cover and try are rolling behind there. If that is the case, close the ashtray, take your hand and hit the side of your console on the passenger or driver side and the coins will lay flat. Open the ashtray and check. You can then use a paper clip or something to pull them out. Hope this helps!
2010 E93 M3 / MS Catless X-Pipe / AA Catback / Vorsteiner Vented Hood and Bootlid E93 Trunk / ADV1 7.1 Wheels GB / LS3 LED Lights / Harrop Supercharger