Boiler issues

Hi, we seem to have some issue with the boiler: unless we turn on the boost the boiler won't heat up he water (during the night the light turns on as it would heat). If we forget and wake up during the night then the timer is on turning on boost is useless.
Anyone had this problem?
Any idea of what could be malfunctioning? the boiler or the box?
This is EXACTLY the issue I've been having for around 6 months.

Did you eventually solve this? Can you share what the cause and solution was?