@Nick ***********
As of last year, a new Thai policy was enacted in compliance with Anti-Money Laundering (AML) regulations. Although this policy is mandatory, some stations are experiencing hardware and staffing issues, which may lead to potential problems when topping up Rabbit Cards.
The new policy requires both foreign nationals and Thai citizens to register or re-register their Rabbit Cards directly at any BTS Station Ticket Office. Most users will only discover this requirement when they attempt to top up their card. Thai citizens need to provide their ID card numbers, email addresses, and contact numbers, while foreigners must physically present their passports to link their card data with their personal ID or passport. This process is designed to enhance security and prevent misuse.
Once your card is registered, you can top it up at the BTS Ticket Office. If you have a Thai cellphone number, you can also top up using the My Rabbit Card app.
I registered my card last year and regularly use the app to top it up. Additionally, the Rabbit Card can be used to ride the BRT Bus, and many Thai food courts accept it as well, sometimes offering discounts for cardholders.
Hope this helps.