Strange behavior of TFT displays using cs pins

Using Arduino Displays
1

I have an esp32 and 2 round TFT displays. They should show the current hour. I read about them and to use multiple displays, you have to wire them in row and connect a CS pin to them. If CS is high → Display can't be written, CS Low → Display can be written. My code just works fine, I even hooked up the cs cable to an LED and it works as intended. But if I hock up the cables to the displays, both displays are updating, showing first the 1. digit of h(1-2) and after that both displays update to the second digit of the hour(0-9)

#include <gpio_viewer.h>
#include <WiFi.h>
#include "time.h"
#include <FS.h>
#include <SPI.h>
#include <TFT_eSPI.h>
#include <Dictionary.h>

#define AA_FONT_SMALL "NotoSansBold15"
#define AA_FONT_LARGE "NotoSansBold36"
//WIFI Keys 
const char* ntpServer = "pool.ntp.org";
const long gmtOffset_sec = 0;
const int daylightOffset_sec = 3600;
TFT_eSPI tft = TFT_eSPI();
GPIOViewer gpio_viewer;

Dictionary<int, String> screenContent;

int current_display_updating = 1;
int num_displays = 2;
int cs_pins[2] = {15, 27};

void setup() {
  for (int i = 0; i < num_displays; i++) {
    screenContent.set(i + 1, "-1");
    pinMode(cs_pins[i], OUTPUT);
    digitalWrite(cs_pins[i], HIGH);  // Initialize all CS pins to HIGH
  }
  pinMode(25, OUTPUT);
  Serial.begin(115200);

  // Connect to Wi-Fi
  Serial.print("Connecting to ");
  Serial.println(ssid);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi connected.");
  WiFi.mode(WIFI_MODE_STA);
  gpio_viewer.begin();
  configTime(gmtOffset_sec, daylightOffset_sec, ntpServer);
  tft.begin();

  tft.setRotation(0);

  if (!SPIFFS.begin()) {
    Serial.println("SPIFFS initialisation failed!");
    while (1) yield();
  }
  Serial.println("\r\nSPIFFS available!");

  // ESP32 will crash if any of the fonts are missing
  bool font_missing = false;
  if (!SPIFFS.exists("/NotoSansBold15.vlw")) font_missing = true;
  if (!SPIFFS.exists("/NotoSansBold36.vlw")) font_missing = true;

  if (font_missing) {
    Serial.println("\r\nFont missing in SPIFFS, did you upload it?");
    while (1) yield();
  } else {
    Serial.println("\r\nFonts found OK.");
  }

  tft.fillScreen(TFT_YELLOW);
  tft.setTextColor(TFT_BLUE, TFT_YELLOW);
  tft.loadFont(AA_FONT_LARGE);
  tft.setCursor(100, 100);
  tft.println("TEST");
}

void loop() {
  digitalWrite(cs_pins[current_display_updating - 1], LOW);
  //Serial.println(current_display_updating);
  delay(5000);
  tft.startWrite();
  String currentHour = getCurrentTime("%H");
  String displayContent[2] = {currentHour.substring(0, 1), currentHour.substring(1, 2)};
  tft.fillScreen(TFT_YELLOW);
  tft.setTextColor(TFT_BLUE, TFT_YELLOW);
  tft.setCursor(100, 100);
  tft.loadFont(AA_FONT_LARGE);
  tft.println(displayContent[current_display_updating - 1]);
  screenContent.set(current_display_updating, displayContent[current_display_updating - 1]);
  tft.endWrite();
  delay(1000);
  digitalWrite(cs_pins[current_display_updating - 1], HIGH);
  current_display_updating++;
  if (current_display_updating > num_displays) {
    current_display_updating = 1;
  }
}

String getCurrentTime(const char* format) {
  struct tm timeinfo;
  if (!getLocalTime(&timeinfo)) {
    return "Failed to obtain time";
  }
  char buffer[80];
  strftime(buffer, sizeof(buffer), format, &timeinfo);
  return String(buffer);
}

Display Esp32
VCC 3V
GND GND
SCC 18
SDA 23
DC 2
CS 15,27
RST 4

I just can't figure out what the problem might be.