For the issue, you are having. May I know if each of the RUT devices is having a dedicated IPSec in the pfsense gateway?
If yes, could you give some information on what configuration you made on the device? A copy of a troubleshoot file of the device that is having problems is good. Don't reboot the device before taking the troubleshoot file. I need to get all the log details, doing a reboot will make erase all the logs of the device since it is stored on the ram memory.