In the morning my heat will not reach the temp setting of 73. It will cut off at 68. In the evening it will reach the temp setting of 73. The furnace and heat setting device is only 2 years old. I do not understand why it works in the evening but not in the morning. Any ideals

Depending on the temperature change you are trying to achieve, you may be tripping the high limit switch. 73 is a pretty high ambient temp and the heater has to really work hard in the morning, possibly overheats the exchanger and the safety trips. In the evening, the ambient temp is higher so the range is less. Try an initial setting of 70 and see if it reaches that. If it does, move it to 73. Where are you located?