When a user adds registration groups in a batch on the eSpace U1910, a registration failure occurs.
Step 1 Run the config ims registermsgctrl switchmode ctrl msgcount 5 command to set the number of registration messages sent by the eSpace U1910 every second to 5.（switchmode isnormal,That does not limit flow）
This method applies to the scenario where the number of registration groups is small. If there are many registration groups, registration may time out when the eSpace U1910 sends five registration messages every second.There is relationship between the configuration and SBC configuration, The general configuration is 5。
Step 2 If the fault persists, contact the service provider.
SBC flow control is not properly configured. As a result, the eSpace U1910 cannot receive registration response messages properly.