How to make sure that one operation does not start until another one has finished?

Question

1C

There is a processing in which the following sequence of operations takes place:
1) Close account 20 -> 2) Close the month (the processing of the Closing of the Month operation opens and the process starts there) -> 3) Adjustment of account 20
I have a problem that the program launches point 2 and does not wait , when the month closes, immediately goes to point 3.
How can this issue be resolved?