We have problems with IPhone X

Hi. We recently bought IPhone X in Almaty in Kcell company. This equipment has some great problems with video reproduction. For instance, I have been watching video and this video returned in some seconds ago every 2-3 minutes. Also we have problems with the sending of SMS. If I want to send SMS to the person in my calling list, it shoul be automatically opened, but sometimes it doesn't work I have to open SMS handily, entering in the SMS section. Could you be so kind to resolve these problems. Is it software problems or is the phone defective.

Sincerely yours,

*****

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