Weird thing- Why GC software did not calculate concentration??

Hi all,

Recently I used a standard to calibrate our 990 Micro GC and input concentration of components in the Level 1 column. After single run, component's concentration displayed In the generated report. I wanna make some changes to peaks so I deleted peaks in peak table  and run "Analyze" . When I added them back in Peak Table with concentration in level 1 and run "Analyze" again, all concentration were gone. There were still Retention Time and Area of these peaks but their concentration were gone!?? Anyone has this issue? See attached picture for reference. Any help is welcome. Thanks. 

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