7 Day Training Load Optimal Range Unrealistic

The correlation between these two graphs over the past month doesn’t make sense: The cycling graph shows two 90km rides in the first two weeks and lots of 50km rides all on the road (not Zwift) yet the training load graph shows the opposite, the graph drops dramatically after first 90km ride and despite consistent 50km rides - despite the ‘optimal’ green line rising in response to training load. The training load graph is way out if sync with actual load.

Start by looking at the training load for those activities. Do you think they make sense? Training load is as far as I know based on heart rate and max heart rate. Do you have correct heart rate data for the activities? Are you using a chest strap? What is your max heart rate and how did you come to that value?

Yes I think the heart rate readings are correct. It’s just the training load graph is out of sync with the actual load…there’s something wrong with the algorithm which is wrongly calculating the load. 

Why would a transition from a 50km ride to a 90km ride cause the training load worm (graph) to go down instead of up?  The 90km ride was significantly harder than the 50!  Then this false reading affects the next reading and so on. 

What training load do you have in those activities? Could you share links to them? It is a lot easier if we can take a look at it instead of asking for each value. 

Well currently, after a hard ride yesterday I’m having a rest day, but Garmin is confused, telling me I’m both Unproductive (Training Status) AND Optimal (Training Load) !  Garmin AI leaves a lot to be desired, even after more than a year of receiving consistent daily data from me, it still thinks I’m someone else! Perhaps an impossible human who can split themselves in two? Bizarre. 

Unproductive means that your VO2 max is sinking and your load is good so those statements by Garmin Connect are true. They should be exactly like that. 

Good training load doesn't mean that your VO2 max will increase. It can go either way. You body is not a machine. It will also take time to change your performance values. Why your VO2 max is going down right now is probably caused by the training you did several weeks ago. Your training load is currently good and you might see an increase in your performance values in a few weeks or months. It depends a lot on where you are in your training. For beginners the increase will go faster than for people that has been training for years.

The VO2 max value can go down 0.1 so you will not even see a change in value since it is an integer in the presentation. You have to look at the arrow next to the VO2 max value in the Training status widget to which direction your VO2 max is moving.

You don't have to constantly increase the training load. That is not how it works. You need to have easy weeks and periods. When the training load goes down you can see an increase in your VO2 max. That is when you are likely to see the training status "Peaking" and you are ready for a race.
Garmin rewards variation in training load. Check the load focus. It is good to have a balance between anaerobic, high and low aerobic activities but that doesn't guarantee that you will get more fit. 

Training status and what they mean: https://www8.garmin.com/manuals/webhelp/fenix5x/EN-US/GUID-6F81BF5B-B49A-4506-95E2-0F4A04D8B319.html

You also need to remember that this device that only can estimate your VO2 max from the data you give it. If you do an exercise under circumstances that will affect your performance in a negative way like running in snow or on ice you will get bad values. For biking it works better since you use a power meter to measure the effort but external circumstances can still affect your performance and give you incorrect values.

It is a very good idea to go to a test clinique and get your values measured by professional equipment so you have the correct max heart rate, lactate threshold, VO2 max, FTP etc. Without correct values it is hard for the watch to give you correct feedback.