How is my device supposed to find my Traccar server?

I have a cheap Chinese kids' smartwatch that is supposed to be used with SeTracker2, and works with that app. However, I'd like to be able to get the GPS coordinates automatically and store a history. AFAIK there is no API for SeTracker2 that allows this.

I installed the Traccar server on my Windows PC and forwarded ports 5000-5300 to my PC on my router. There are two numbers printed on my device, the IMEI and "reg gode" (I'm assuming this is supposed to be "reg code"). I created two device in Traccar on the web interface with those numbers as ID, one for each number. Nothing happens, and nothing is in the logs.

What I don't understand is how my device is supposed to find my server. I can't configure a server IP address or anything like that in my device. Is that possible with other devices? Does Traccar find the device's IP address from the IMEI number somehow? How is that supposed to work?

Thanks in advance for any answers!

Update: I found out that my device (which seems to be a Wonlex KT12) can be accessed over SMS. If I send "pw,123456,ts#", I get the following info (I censored the IMEI censored):

ver:G4C_XT_EMMC_240_5M_LS_En_N_2021.09.25_19.12.00; 
ID:9024028978; 
imei:***************; 
url:52.28.132.157; 
port:8001; 
upload:60; 
lk:300; 
batlevel:91; 
language:en; 
zone:+02:00; 
profile:1; 
GPS:OK(0); 
wifiOpen:true; 
wifiConnect:false; 
gprsOpen:true; 
NET:OK(100)

Apparently 52.28.132.157 is the IP it sends its coordinates to, and it belongs to SeTracker. I'd like to replace this with my local Traccar server. I tried with the command "pw,123456,ip,1.2.3.4,5093#" (with my external IP where 1.2.3.4 is), but the fields "url" and "port" do not change, nor does anything appear in my Traccar log.

Does anyone know how to successfully change the server IP in this device?

Are you sure the command is correct? Is it from the device manual?

Maybe your device is locked to a specific server?

Wonlex KT12 have fixed ip which can not be changed through sms. They use this locking method in newer firmwares for security reasons. And also for watches / trackers that can do Video calling. Its possible to change the ip with a new firmware update but surely you wont be able to acquire the tools for that if your not a reseller.
Also your watch will use data encryption for data transfer between the server and the watch, so it wont work either since there is no encryption protocol provided with a standard traccar server.
So if you are looking for another watch, then ask a reseller for a watch that does not use encryption and where the ip and port can be changed. Commonly older models like q50 and q90 etc can do that.

locking method in newer firmwares for security reasons

I'm pretty sure security is not the main reason. They probably want to lock people in their service.

I understand your idear. But using their tracking services and app are without any costs for the customers. So i guess it would be cheaper for them when people use their devices on their own server like traccar.

There's at least a privacy cost.

Thats true, and they might push adds through their app. Not that i am in favor of fixed ip either.

Thanks for the answers! A pity that it can't be reprogrammed to use Traccar.