Update-
After more than 60 hours, coinbase refund me. I thank their support although it was a bit late. I wouldn't mind to use coinbase but occasionally. I wouldn't recommend anyone to use it for regular transactions.
Here is one more reason-
Coinbase asks for a verification code when sending balance. In case, if you don't enable 2FA, code will be sent through your sim. I have faced problem once, the code wasn't in my sim for more than 2 hours, as a result, I was not able to send BTC.
After all, a big thank to them for the refund.
I want to tell something here,
60 hours is not too long when compared to the reply from support team of many reputed exchanges,even it might take weeks for the replies to arrive.And 2FA is a problem for me in coinbase and it happens because of the low network coverage on your device,if you face it then remove that sim and insert it to other will take those codes to arrive.