Rakuten complaint: Instead of giving my cash back the Rakuten deactivates my account

I am a member of the Rakuten since November, 2020. In 2021 I made 2 transactions via the Rakuten and earned USD 20. Later in 2022 USD 8 dollars were written off as an Account Maintenace Fee.
In February 2023 I wrote an email to Customer Service of the Rakuten asking for assistance in getting my remaining (USD 12) cash back.
I have not been receiving my money back for 3 years and instead of helping me with the issue I received email from Member Operations Analyst stating that my account was deactivated, and I will not get my money back.
After few correspondences and requests to provide me with clear reason for deactivation and nonpayment my money back they informed that my account had a high level of abuse. What sort of abuse my account did and how nobody explained. The article they provided as a reference (Terms Conditions) was very vague and I could not relate it to my account.
Eventually, it looked as the Rakuten did not want to pay my money back and is ready to provide any reason for this. Three years they kept my money to say at the end that my account is going to be deactivated and I would not receive anything from them.
It is not the best way to deal with the clients and I consider this action against me as a robbery. Though a cash back amount is not large it is money that I earned, and I want justice for my case.