Preferences preferences;

void setup() {
Serial.begin(115200);
Serial.println();

// Open Preferences with my-app namespace. Each application module, library, etc
// has to use a namespace name to prevent key name collisions. We will open storage in
// RW-mode (second parameter has to be false).
// Note: Namespace name is limited to 15 chars.
preferences.begin("my-app", false);

// Remove all preferences under the opened namespace
//preferences.clear();

// Or remove the counter key only
//preferences.remove("counter");

// Get the counter value, if the key does not exist, return a default value of 0
// Note: Key name is limited to 15 chars.
unsigned int counter = preferences.getUInt("counter", 0);

// Increase counter by 1
counter++;

// Print the counter to Serial Monitor
Serial.printf("Current counter value: %u\n", counter);

// Store the counter to the Preferences
preferences.putUInt("counter", counter);

// Close the Preferences
preferences.end();

// Wait 10 seconds
Serial.println("Restarting in 10 seconds...");
delay(10000);

// Restart ESP
ESP.restart();
}

void loop() {}