I have been a Marriot/Starwood member since 1999. This is our 3rd trip to this hotel within the last 2 years, however, this trip we have experienced terrible service. Throughout the trip, housekeeping was a real issue. This initially started with minor problems. As it is now wintertime in Montreal, dirt residue from our boots were left on the floor. In addition, our dirty glasses and tissues have not been replenished, and the bed sheets have not been changed. On the third night, we went out the whole day from 6am to 2pm, and the room was not cleaned for the entire day. We stayed in the room from 2pm to 4pm and left the room without the do not disturb sign. When we came back at 7pm, the room was still not cleaned. We then called room service to request our room to be cleaned, and they replied saying that the housekeeping service had stopped. In response to this, we went down to the reception and complained to the front desk staff, who then called guest service manager HYUNJUN KIM. Mr. KIM replied with a condescending and sarcastic tone and kept on repeating that our room was not available for the housekeeping service's time. We replied that when our room had the do not disturb sign for 2 hours, they could have contacted us through the phone/messages to tell us our room was not available for them to clean. Overall, we found that Mr. KIM's responses were unprofessional and very rude, as we feel very insulted that he constantly tried to make a mockery out of us. However, they did provide us with new towels and tissue paper for the night.