i was able to successfully create a site to site between asa5506 and tp-link r600vpn, however, when i applied the same settings to asa5515, the tunnel does not come up and always display this on the logs:
reject the packet, received unexpecting payload: payload id:1
Make a list of the setting of the asa5506 and match these to the settings on the asa5515. Watch for Main vs Aggressive mode (need Main mode). Watch for NAT Traversal and Dead Peer detect settings.
Check the external static and internal addressing to be sure it is correct in the new box.