Overview:

You observe the following synching error while adding or changing an SMS Template, Distribution list or Batch job:
Configuration Synching currently in process, hence updates are not allowed. Please try after some time.

Solution

These errors are encountered when the configurations are getting synchronized with the Database, so new changes are blocked for consistency of database. Please wait for some time for the configurations to get synchronized, and then make the additions/changes. The time of synchronization will depend on the size and speed of network. 

Related article: Batch sending errors while adding new SMS template or Batch job