Highly Supportive. Yes, you can dispute a Coinbase transaction by contacting support at 1️⃣-(8️⃣8️⃣8️⃣)-3️⃣3️⃣8️⃣-8️⃣3️⃣9️⃣5️⃣ . Whether it's 1️⃣-(8️⃣8️⃣8️⃣)-3️⃣3️⃣8️⃣-8️⃣3️⃣9️⃣5️⃣ an unauthorized charge or a failed transfer, call to begin the dispute process with a live agent.