Sometimes, there are people surfing the web when your phone suddenly "bad", the 3G/4G network speed suddenly becomes extremely slow even though the data traffic is still full, making us very uncomfortable. So when facing this problem, how to fix it? Here are some measures to help you quickly solve 3G/4G network speed problems on your phone through a few very simple steps.

Often when you are using 3G, 4G Internet on mobile, you see the letter E appear, which means the network signal is flickering, this can happen when you are in a remote area, the The phone signal area is not yet covered. But if the speed is normal and suddenly becomes weak, the error may be caused by your phone. Try the following to fix it:

1. Switch your phone to Airplane mode

With Android, you swipe from the top of the screen to open the Quick Settings panel, tap the Airplane icon, and wait for the phone to completely disconnect from Wi-Fi and cellular connections. Wait about 30 seconds and click the plane icon again.

For iPhone users, open Control Center by swiping down from the top-right corner of the screen if it's iPhone X or later, while older models will swipe up from the bottom. Then wait about 1 minute between tapping the plane icon for the network to work properly again.

2. Switch back to priority network mode (usually this is due to weak signal or you are in 2G mode for sim)

Setting your phone to mobile data will allow you to use the mobile network in 2G mode, 3G mode, 4G mode, or use 3G and 4G in parallel. In case you are in an area with 3G waves but in 2G mode, the speed cannot reach the highest level, the letter E will be displayed.

To overcome this situation, you just need to go to Settings> Mobile network> Preferred network type / Network mode…> Select only use 3G if you need high speed to use, select 3G / 2G automatically if you want to save battery and the area where you live has a strong, stable 3G network signal.

For iPhone, go to Settings > Cellular > Cellular Data Options.

Select Voice & Data. Here you choose the desired network mode.

3. Check carrier settings and reset network settings

For iPhone users alone, Apple's network signal troubleshooting support page recommends a few tips, but in general there are 2 ways:

If you've been using your iPhone for a while, you'll likely get a notification that your carrier settings are up to date. These updates help iPhone optimize connections.

The first way: force iPhone to check for carrier settings updates, open Settings > General > About. If an update is available, you will be prompted to install it.

Open shipping settings to optimize iPhone connection.

The second way is to reset the network settings. By going to Settings > General > Reset > Reset Network Settings, this will reset any saved Wi-Fi passwords, VPN connections…Once confirmed, your phone will reboot on its own. .

Resetting network settings will restore all of your iPhone's connection passwords.

But sometimes the poor signal can originate directly from the network provider. Cell tower collapses, broken fiber optic cables are common causes. If the exact cause is determined from here, immediately contact the carrier to be resolved.

4. Set strong data mode for phones 

Smartphones usually have 3G pre-installed, but some smartphones, although pre-installed with network data mode, are in GSM mode, which is a normal mobile network (2G), speed the access speed will be slower than 3G. So you need to set up WCDMA/GSM auto mode so that your device automatically switches 2G, 3G depending on the coverage area where you use 3G service.

Step 1: Go to the Settings Menu.

Step 2: You scroll down, find More networks or Add (depending on the phone you use).

Step 3: Select Mobile networks, then select Network data mode.

Step 4: Select WCDMA/GSM (auto connect).

If you choose 1 of the 2 remaining items, every time you change your location to a strong or weak signal area, your 3G condition will be unstable and will lead to inaccessibility. Remember to select the auto-connect option.

5. Restart the phone

Smartphone is a miniature computer. Just like momy calculator, you can sometimes fix the problem by rebooting. It's best to do one of the above and then restart your computer to make sure the changes take effect.

6. Remove the SIM

With this method, users of all phone models just need to remove and check if the SIM card is damaged or has been properly placed in the slot.

In some new phones, users will need a stick to open the SIM slot. However, with smartphones that use the built-in eSIM in the phone, you cannot use this method.

Above are 6 simple ways you can do it easily in "tick" to overcome the problem of unexpectedly weak 3G/4G network speed after a period of use. If you still can't fix it, you can turn off mobile data for a while and then turn it back on to see if that changes anything. In case the problem is more serious i.e. the network speed is very weak or you cannot access the network for a long time, seek help from reputable phone service and repair centers.