The timer handling changed in the ESP32 Arduino libraries, see documentation:

https://docs.espressif.com/projects/arduino-esp32/en/latest/api/timer.html

src/platforms/esp32.h

@@ -47,19 +47,16 @@ void initTimer(uint32_t init_clock)
     // create the clockTask
     xTaskCreate(clockTask, "clockTask", CLOCK_STACK_SIZE, NULL, 1, &taskHandle);
 
-    _uclockTimer = timerBegin(TIMER_ID, 80, true);
+    _uclockTimer = timerBegin(1000000);
 
     // attach to generic uclock ISR
-    timerAttachInterrupt(_uclockTimer, &handlerISR, false);
+    timerAttachInterrupt(_uclockTimer, &handlerISR);
 
     // init clock tick time
-    timerAlarmWrite(_uclockTimer, init_clock, true); 
+    timerAlarm(_uclockTimer, init_clock, true, 0); 
-
-    // activate it!
-    timerAlarmEnable(_uclockTimer);
 }
 
 void setTimer(uint32_t us_interval)
 {
-    timerAlarmWrite(_uclockTimer, us_interval, true); 
+    timerAlarm(_uclockTimer, us_interval, true, 0); 
 }