Hello Eswaran,
how the parameters in the method are set, which is configured for the affected RFC destinations?
Please ensure, that the parameter MTE_CLASS is set to a unique MTE class name in each method for the monitoring of the RFC availability, and that the parameter COLL_METHOD is set to the method name itself (and not to the name of the original method CCMS_RFCDest_Availability_Coll). This is the cause in the most cases, the both parameters are configured incorrectly and because of this the RFC availability is displayed as 0%. In case you will change parameter settings you will need to delete the availability monitor structure in RZ20 with option 4 and recreate it by reseting the segment with the Availability context in "WARMUP" status in RZ21.
Regards,
Alwina