MPU6050 gets distracted by TFT Display?

Hello,
I tried to show the angle given by my MPU6050 on a 3,5" TFT display. First, here's my code:

#include <MPU6050_tockn.h>
#include "Dash.h"

MPU6050 mpu6050(Wire);

Dash dash;

 
void setup() {
  Serial.begin(9600);
  
  Wire.begin();
  mpu6050.begin();
  mpu6050.calcGyroOffsets(true);

  dash.init();
}


void loop() {
  mpu6050.update();
  Serial.print("angleX : ");
  Serial.print(mpu6050.getAngleX());
  Serial.print("\tangleY : ");
  Serial.print(mpu6050.getAngleY());
  Serial.print("\tangleZ : ");
  Serial.println(mpu6050.getAngleZ());

  dash.printNr(0, 0, mpu6050.getAngleX());

  delay(50);
}

In the loop() I first update the MPU and then print the value on my Display.
Here's the dash.cpp

#include "dash.h"

//define some colour values
#define BLACK   0x0000
#define BLUE    0x001F
#define RED     0xF800
#define GREEN   0x07E0
#define CYAN    0x07FF
#define MAGENTA 0xF81F
#define YELLOW  0xFFE0

#include <LCDWIKI_GUI.h> //Core graphics library
#include <LCDWIKI_KBV.h> //Hardware-specific library

LCDWIKI_KBV lcd(320,480,A3,A2,A1,A0,A4);//width,height,cs,cd,wr,rd,reset

void Dash::init() {
  lcd.Init_LCD();
  lcd.Fill_Screen(BLACK);
}

void Dash::printNr(int h, int v, float nr) {
  lcd.Set_Text_Mode(0);
  //display 1 times string
  lcd.Fill_Screen(0x0000);
  lcd.Set_Text_colour(RED);
  lcd.Set_Text_Back_colour(BLACK);
  lcd.Set_Text_Size(5);
  lcd.Print_Number_Float(nr, 2, 0, 8, '.', 0, ' ');
  //lcd.Print_Number_Float(01234.56789, 2, 0, 8, '.', 0, ' ');  
  //lcd.Print_Number_Int(0xDEADBEF, 0, 16, 0, ' ',16);
}

Now the problem is, when I use the display, the value isn't correct, if I don't move the MPU, it slowly gets higher and higher, and if I move it, it completely gets crazy. The strange thing is, if I don't use the display (I only commented all code of the dash out), then it works fine. The display is on and shows only a white screen, but I don't use it.
So could it be, that maybe some magnetic field or anything of the display is distracting the MPU?
Or is it possible that it is because of the fact, that they use the same ground and 5V?

Some more information:
I use a Arduino Eleego Mega 2560, this tft display and this MPU6050. The display is directly plugged on the Arduino, the MPU 6050 is soldered between the display and the Arduino. Next to the MPU, there is also a bluetooth Modul, not in use, so I think it shouldn't cause the error.

I hope someone can help me, hopefully it's only a code problem.
Thanks
Sek

Get all the pieces of the project working individually, before trying to put them together. Make sure you understand how the MPU6050 works, using just the serial monitor for output.

Then learn how the TFT display works alone, and add that in to the project.

You might find the TFT display is overloading your 5V supply and that's causing unstable power to the MPU6050 - check that the 5V supply is stable with the TFT connected - backlights take quite a bit of power on a large display.