Did you check SETTINGS, then select ECO heating and cooling temperature
settings? Since you said it happens frequently at night, maybe the ECO
heat temperature setting is 70 and it is overriding your manual setting
of 64. Also check the SCHEDULE feat...
Go to SETTINGS, then ECO to see the heating and cooling temperature
settings. These settings override your manual settings. Change these
settings so that they are beyond the settings of your manual settings if
you want the manual settings to have pri...