At approximately 930am I arrived at Memory Care.  I met with the director of the facility and she directed me to where my team would be setting up.  My team consisted of (technician), (nurse) and I. As we were setting up, the director asked how she can help. I explained to her that we would need a designated area for patients to be monitored after vaccination for 15 minutes and maybe even longer . I also explained that we would need one of her staff monitoring while we vaccinate. She agreed, and proceeded to designate her staff and the cafeteria area, facing the vaccination station,the monitoring station.   Throughout the day, nurse and I were both vaccinating,while the staff of the facility would monitor the vaccinated patients. I would also stop occasionally to mix the vaccine and check the temperature of the aero safe.   At approximately 12:50pm, the director rushed in and stated that a patient is not responding, and that she had been vaccinated. At that point, I grabbed epipens and a thermometer and I also instructed nurse to grab an Epipen and come with me. We followed the director to pt's room. Once we got to the room, the patient was in bed and there were 4 staff members standing bedside and one of them turned and stated the patient has passed. At that point I asked the staff how long ago did the patient get the vaccine, they stated about 30 minutes ago. They also stated that the patient was a hospice patient and that the patient had declined, and was rapidly detiorating and had not eaten or drank anything all day . They also stated that the patient had been monitored for 15 minutes post vaccination. I then left the room and grabbed the patients COVID Vaccine intake consent form.     I looked at the answered questionaire and all the responses were circled NO. Patient had a temp of 96.5 at the time of vaccination.The vaccine administration information for Immunizer Section was filled out by Nurse. I then proceeded to ask the director once again if there were staff that was monitoring her for 15 minutes, the director stated they had staff monitoring her. She also stated the Hospice nurse has to announce her death, so they waited for the Hospice Nurse to come.  I then called Corporate and explained the situation. After speaking to corporate, I also asked nurse, if she remembered the patient. She stated that she did and at the time of the vaccination the patient was not alert, there were two staff members with the patient. She was non oriented and she kept closing her eyes. At that point, Nurse stated that she asked the two staff members with her if this is how she usually is and if its ok to vaccinate her. Both Staff members stated that it its ok,this is how she is. The Nurse then proceeded to vaccinate.  At approximately 3:10pm, as I was leaving I spoke to the director, and one of her Staff members. Staff that the patient has actually not eaten/ or drank anything for the past several days, including today(01/18/21). Staff also stated that on Friday, Jan 15th,2021, they had informed the family that the patient was rapidly detiorating. Staff also stated that the family knowingly gave the consent to vaccinate her. She also stated that the hospice Nurse believes that the death was primarily caused by her detiorating state. She also stated that the hospice Nurse informed that the death was not due to the Vaccine. Per Lead Pharmacist at the clinic.