All Inbound queues going into CPICERR error

Hi Experts,

After the MW set up, I see that all the inbound queues are getting stuck with the CPICERR error and when I double click on it. It gives the message "RFC destination 30 does not exist." Though if I unlock the queues, it is getting processed but ideally, it should not go into CPICERR error and should automatically get processed. I have checked SM59 and BD97 and noticed that RFC destination has been correctly maintained. Could you please suggest, what is root cause and where I am missing out.

Regards

Miller