There's probably probably something in your code that prevents the array from being updated straight away.. My guess is that it's a data flow problem. Let's say e.g. that the array you are looking at is wired to the output of a VI, a shift register, or through the side of a loop, case or sequence...then the array does not really receive the new data until everything inside that structure (VI/loop etc...) is finished running. LabVIEW does not release the data coming out of such structures until all outputs of that structure is ready...so you need to put the indicator inside that "border" or use a local/global (functional) to see the data on the fly...
If you could take a picture of the code; showing the array terminal /wires and the data source ...or a copy of the VI(s
) that would help pin-point the problem.