MO-MT CSFB Issue

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Question:-Incoming csfb on B party is failing and A party hears number busy, however csfb is successful for B party when originates voice call

Answer:- wrong LAC-TAC mapping at B party

When you see at A party you will find that core Network is not able to find B party LAC CI that is the reason such  Announcements are playing " Logical announcement should be not reachable but usually core does such mistakes that map same announcement with some set of clear codes at CS core "

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