(1) I divorce my wife three times in one sitting; I believe that the talaq is valid but my ex-wife is not accepting the talaq.
(2) I got a valid reason to divorce her, on behalf that only I divorced her.
(3) At the time of divorce, around ten members were there from both the sides. Please help me to come out from this problem.
بسم الله الرحمن الرحيم
When you have surely given three talaqs to your wife in the presence of ten persons then all the three talaqs took place and your wife became irrevocably divorced (mughallazah bayina) and haram for you. Talaq shall take place and it does not have any impact on talaq whether she accepts it or not. Do not have any doubt. Talaq does not depend on the confirmation of the wife, as soon as the husband pronounces the word of talaq, it takes place immediately.
Allah knows Best!
Darul Uloom Deoband