Is your new 20 Release 5.0? If it is, and your old 50 was release 4.0, did you use the 4.0 backup to restore the R5 box? If so, you will likely have to reprogram the Parking Lot parameters. I know I had to when I did it on one. The Alternate location will likely be set to Terminate call if you didn't already change it. If your timing parameters are not correct, you might get that very condition.
I will assume that you already tried a power off reboot.