Viber Seized My Money on the App

Viber app blocked my account out of the blue, claiming it is spam and stating in an email that it is irreversible. I couldn't understand why it is irreversible, but I thought Viber is not important in my life since there are tons of similar apps that I can use, so I didn't pursue making them open my account again. I sent an email stating that I want back my outstanding balance in my account, but they're ignoring my request. I sent them several emails and mentioned them on Twitter, asking for my money back that they inappropriately seized from my remaining balance in the app. Now, I want my money back from Viber and the responsible company, Rakuten.