Vo2 max has not updated since first run

How do you know it has not updated? It is something that moves very slowly. Especially when the metrics presented are largely in whole digits.

It can take me months to move it one whole digit 

If you use runalyze you can see the VO2max from fit file to two decimals  (if you select that option in settings) , or you can use a fit file viewer to see the Vo2 Max recorder to a number of decimals 

It has not tracked a vo2 value since March 13th

What do you mean with not tracked? Not changed? As S.M.R. mentioned earlier it can take months for VO2max to change. Anecdotal but mine only went up by one after half a year of consistent running.

The last and only tracking point I have on Garmin connect is march 13th but as I said I went on multiple runs since then. I am new to running and got a Vo2 max of 56 which seems really high and I would like to know at least it's not just a one time run number and actually an average of my performance.

I guess that you have read this:  https://support.garmin.com/en-US/?faq=lWqSVlq3w76z5WoihLy5f8

Note that you do need to run at over 70% MaxHR for at least 15mins, so, for example, a Zone 2 training run may not trigger that threshold.

I am typically seeing an update to VO2 Max (under Perfomance Stats in the Connect phone app) about 1 to 2 times per week, based on 3 to 4 runs per week.