Hi @Anonymous .
I have made a test on my side to create a sharepoint list as below:

The Frequency column and Status Column are both choice type column.
Frequency column with choice:Annually, Quarterly, Monthly, Semi-Annually
Status Column with choice:Completed,NotCompleted
And you could refer to screenshot below to create the flow:

Note:
1.Make sure to choose the Status Value dynamic content in the Condition.
2. The expression in the Compose as below:
if(equals(triggerBody()?['Frequency']?['Value'],'Annually'),int(12),if(equals(triggerBody()?['Frequency']?['Value'],'Quarterly'),int(3),if(equals(triggerBody()?['Frequency']?['Value'],'Monthly'),int(1),if(equals(triggerBody()?['Frequency']?['Value'],'Semi-Annually'),int(6),null))))
3.The expression in the Due Date column as below:
addToTime(triggerBody()?['Due_x0020_Date'],outputs('Compose'),'Month')
When an item is created in the list as below:

The flow would run successfully as below:


An item would be created in the sharepoint list as below:
Best regards,
Community Support Team _ Alice Zhang
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