In the police station Kumkum and Sharman were there Tiple gets some message may be that message was from Nivi telling after knowing the plan from Sukanya and thats why Tiple got Saavdhaan.
Another thing, remember in the Bar Tiple told Katara on the phone that he is coming to take him. So instead of getting the number that could have followed Tiple, but I guess for that may not have enough time.