It depends—fiat transactions may be refundable 1️⃣ー8️⃣8️⃣8️⃣ー4️⃣1️⃣9️⃣ー9️⃣7️⃣6️⃣2️⃣ , but ????rypto transactions are not. https://www.dfrobot.com/forum/topic/384670