I Can't Complete Calls on My Oppo X7 — Calls Drop After 30 Seconds

I purchased the Oppo X7 just two weeks ago, and since day one, I've been dealing with a serious issue: every phone call disconnects after exactly 30 seconds. It doesn’t matter if I'm using Wi-Fi calling, mobile data, or a regular GSM connection—the result is always the same. This isn’t an occasional glitch; it’s consistent and incredibly frustrating.

What’s worse is that this appears to be a widespread issue, as I've seen many others reporting the same problem online. Some have even sent their phones to service, but they say nothing improved after the return. I rely heavily on my phone for work, and this flaw has made it almost impossible to handle important calls.

I’m extremely disappointed in Oppo’s quality control and lack of action. This is unacceptable for a new phone, especially when it's affecting basic functionality like making calls. I urge Oppo to acknowledge this defect, provide an immediate fix—whether through a software update or device replacement—and stop leaving customers in the dark. A premium phone should not come with such a fundamental flaw.