Wacom Intous Pro Small PTH-460 Pen pressure doesn't go up to 100% pen pressure no matter how hard i press it.

When using my pro pen 2 the pressure doesn't reach 100 % . when i tested it in wacom diagnostics with default setting, it only reach 63% for both pen and eraser. Is there a fix for this? or should I just return it ? since its still under warranty.