Turn off your Samsung Galaxy Z Flip 4 and Z Fold 4. Press two buttons simultaneously – V olume Up + Power Key for a few seconds until the phone doesn’t vibrate. Go to “Wipe cache partition” from the given options using the volume up keys and select it using the power button. You will get a pop-up menu with the different options you can choose from. Ensure that you select the first option that says 4G/3G/2G (auto connect). Selecting this will ensure that your device is connected to the correct network. Solution 6: Clear SIM Card Manager Cache Fannyslapper--you don't know what you're talking about. The Galaxy S4 is required by the FCC to be unlocked for international use. I used a French Sim Card in my S4 this past fall in Paris--it worked for phone and SMS but I could not get it to work for Data, though I was able to input the APN for my French Carrier, Lebara Mobile. That normally brings stuff back together. If that doesn't work, the ##72786# (redoes the PRL, Update Profile, Hands Free Activation). BUT that sometimes doesn't work. Gosh, it's like working with Microsoft products reboot to see if the problem clears up. Hi all, I'm in Italy and I am trying to use a Vodafone SIM card with my Verizon-purchased Samsung Galaxy S4. I have been assured that my phone is Globally unlocked, but it refuses to recognize the SIM card, saying that it is a non-Verizon SIM and that it is from an unknown source. Then, I tried to c Good Android phone with 2.3GHz Quad-core processor provides good performance and great system execution of the Samsung Galaxy S4 (GT-i9506). With one SIM card slot, the Samsung Galaxy S4 (GT-i9506) allows download up to 150 Mbps for internet browsing, but it also depends on the carrier. 5" 16M-color 1080p Super AMOLED capacitive touchscreen with Gorilla Glass 3. Android OS v4.2.2 Jelly Bean with TouchWiz UI. Quad-core 1.9 GHz Krait 300 CPU, Adreno 320 GPU; Qualcomm Snapdragon 600 To boot your Galaxy Tab S4 to safe mode: Turn the device off. Press and hold the Power key. When Samsung appears on the screen, release the Power key. Immediately after releasing the Power key PQksf4.