You may have to clear the array then use a for loop to add as many elements as you need.
Set the last index to be your length - 1
You can also clear is then use the set array element node and tell it to resize the array.
Set the index on that node to be your length - 1
The first method lets you set the data at the same time
The second one would just make the array the right size and you’d have to set the data yourself after.