Switching minoxidil from twice a day to once a day, is this a problem?

I recently switched to once a day from two because of some reasons. After that I saw heavy hairfall on my head and made me anxious. I used to head bath daily in the morning and I didn’t do shower from the day i switched to once a day of minoxidil.Is the sudden hairfall because of change of minoxidil application or any other possible reasons.

I tell my patients that once a day minoxidil is fine if you put it on at night after a hot shower and leave it on all night so switching twice a day to once a day with this routine should not be a problem