Incorrect value obtained from mqtt

Using Arduino Programming Questions
1

I am having an issue with a received mqtt topic value and I think it might be due to the int conversion below:

void callback(char* topic, byte* payload, unsigned int length) {
  int value = String((char*) payload).toInt();
  String topicString = String(topic);
  Serial.print("Message arrived [");
  Serial.print(topic);
  Serial.print("] ");
  Serial.print("Value [");
  Serial.println(value);
  Serial.print("] ");

The problem is that I can always see the correct via mqtt explorer, i.e. 5000 but sometimes (not always) my value is read as 50000.
As a work around I am just diving by 10 if the value is > 10000 but that's not right, I need to fix the value conversion, can someone see anything wrong with that? Or suggest alternatives?

2

Print the payload to serial too, so you can verify that the number from MQTT is correct.

3

Hmm I tried and got this:

 error: call of overloaded 'println(byte*&)' is ambiguous

   Serial.println(payload);

Which is the proper way of calling that?

4

try:

Serial.println((char*)payload);
5

Not sure if it is the cause but I see an extra t at the end?

[13:37:55]] Extending for 5000 msMessage arrived [home/left-recliner/extend] Payload [50000t
[13:37:55]] Value [50000

50000t is the result of printing the payload it seems.
I send the payload via Home Assistant to the mqtt topic.

Sometimes it even gets 500000 instead of the 5000 value:

[13:49:31]] Extending for 10000 msMessage arrived [home/left-recliner/extend] Payload [500000
[13:49:31]] Value [500000

And the value is always correct ok in MQTT explorer so I have no idea.
This the raw YAML for HA that I call, maybe I need to formulate my payload differently? Like JSON?:

service: mqtt.publish
data:
  topic: home/left-recliner/retract
  payload: '5000'
6

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