Answer:
identify the problem.
Explanation:
Identify the problem -
It refers to the method to determine the root cause of the issue , is referred to as " identity the problem " .
Hence , from the given scenario of the question,
The manager first need to detect and determine the issue rather than taking any prompt action , which might increase the issue further .
Hence , it is best suited to first identify the problem which is reducing the number of customers , and then rectify it by using proper steps .