Set date to 1st day of next month based on other field

[Chenab Khanna]

Hi,

I have 2 date/time fields (say, A & b) and need to set value on 1 field based on other.

So, whatever date/time value user selects manually in field A, then field B should be auto populated with 1st day of next month.

For eg, if user selects value of A as 4th april,2021 23:00:00, then value of B should be 1st May,2021 00:00:00.

1st will be constant for every value of A, only the month will change depending on month selected in A. Time will also remain constant as 00:00:00AM

Can someone help me with this?

[Sai Kumar B]

var day = getMonth.getDayOfMonthLocalTime();

can you try this?

[Chenab Khanna]

Did not work