Thanks for reaching out to us for support.
Regarding your concern, upon checking the specifications and settings on the Samsung Galaxy Prevail™ Android Smartphone (SPH-M820), there isn't an option available to disable the lock that appears when a call is made. This feature will prevent the call from disconnecting when you put the handset near your ear and accidentally touch your cheek. However, you can unlock the screen for you navigate the phone even while on call by pressing the lock key.
In regards to your second question, please reach out to your carrier. Any network related issues can be troubleshooted by your service provider.
If you need further assistance, please call Samsung Customer Support by phone at our toll free number 1-888-987-4357, between the hours of 7:00 a.m. to 9:00 p.m. Monday through Friday, and 9:00 a.m. to 6:00 p.m. Saturday, Central Standard Time.
For future inquiries, you may also contact us via Twitter or Facebook.
Follow us on Twitter @galaxyssupport or @samsungservice
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Thanks and have a great day!
Samsung Mobile Technical Support
answered 2 years, 10 months ago
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