While Scheduling a report to be send as mail attachment ( PNG Format ), the look of the Graph in the Report mode is fine and all is readable and of correct size , but in the mail as PNG file format is different and not readable type. ( Big Graph , small labels text /not readable)
The issue is not with our platform but rather the charting engine that we use. Highcharts has a limitation where if there is a lack of space to display the data label, it will remove it so that data labels do not overlap and there is no confusion with what the data label is representing.
Try to avoid long label and column descriptions in order to maintain text as legible as possible on all orientations.