Coinbase does offer 24-hour customer service. you can reach their customer service by calling their phone number, +1 (833)-224-8397 (𝟐𝟒*𝟕 𝐋𝐢𝐯𝐞 𝐏𝐞𝐫𝐬𝐨𝐧) 𝓸𝓻 +1 (833)-224-8397 [𝓡𝓮𝓪𝓬𝓱 𝓛𝓲𝓿𝓮 𝓟𝓮𝓻𝓼𝓸𝓷], 24 hours.