Hi SoparM,
Sorry for the delay, I was able to replicate this case with your desired result by following the video tutorial you have provided me.
The reason why you were not getting your desired result is because the chart counts the data series (Grade) from the primary table (with Min/Mid/Max) as 1 to 6, even if you are seeing it as 9 to 14. Then, when you add the Grade as data series from your second table, the chart counts it as it is (9-14). As a result, the dots (Scatter) appeared on the right side of the chart.
A workaround for this is to replace Grades 9 to 14 from the second table with 1 to 6, respectively. In that way, it forces the Grade data series to align accordingly with the primary table. Please see attached for your reference.
Please let me know if it worked out well for you. If not, please reply back to this forum to let me know and I will be glad to follow up and help you further.
Thank you and stay safe!
John