Hi Waseem,
a VLS-GXL license has 12 tokens.
For running Virtuoso you need 4 token. The Analog Auto Placer requires additional 8 token. When starting the Auto Placer you must be sure that these 8 tokens are available. If you run 2 Virtuoso sessions then there are only 4 tokens left. Exit one Virtuoso session and then start the Auto Placer.
Regards
Werner