Telegram Channel - Fraudent through Telegram app

I am working on an online gaming application. And I was given the task of promoting the app through social media influencers. On **th October ****, I received a mail from an influencer from the telegram App. And he stated that he could promote our app in * of his Telegram channels for **k during the ICC T** world cup tournament. After discussing the proposal, we sent him the contract and he signed it. But when we made him the advance payment of **K to his PNB bank account. He told us that he didn’t receive it and the bank had some server issues. This conversation went on for *-* days, so instead, we took initiation and contacted the branch where we sent the amount and got the information that the amount was already credited to his account on the same day (**th October ****). After getting the update when we contacted him he confessed that he had received it but was busy with other work and told us that the next day he will start the campaign. But after * he stopped posting and started violating our contract by promoting another app. When we got to him to talk about he started to stop answering our calls and mail. So, we told him that we are going to move legally, then he told us that he can’t run our campaign and will refund our advance money by **th December ****. But to date, we have not received the money and he is being very arrogant with us saying that he will give us the money when the wishes. Due to this, we have lost all our trust in any social media influencer to work with. The main issue is the arrogance of the guy as it’s like we are asking him for his money from him rather. I am giving the channels of the influencer below . Request anyone reading it may take the best actions against him.

https://t.me/Bluechip***
https://t.me/Tosspassearnings
https://t.me/bettingearning***
https://t.me/megaparisurebet
https://t.me/helabetworldbetting
https://t.me/Matchfixerinfo
https://t.me/melbet_megapari_bet***_parimatch
https://t.me/Luckeyjetexpert