Hello.. My name is Jit. I bought Samsung S4 in last july. From last 2 months when my friends are calling me sometime call directly going to voice mail. 2 out of 10 calls are having this issue. My friend also has same phone from different carrier and he is also has same issue. I contact Samsung support they told me this is carrier issue. Then contact Koodo customer service they told me there is no any issue on your phone. Any fix for this ?