HTTP SMS Gateway Provider SMS77.io

Hello everyone,
I tried everything to set up the HTTP SMS gateway from the provider SMS77.io.
I need help entering the correct commands in the config file.
the link to help from the provider SMS77.io.
https://www.sms77.io/en/docs/gateway/http-api/
Many thanks for the support.
Best regards
Guido Bonewitz-Raband

What have you tried?

I tried the following entries:

     <entry key='notificator.types'>web,mail,sms</entry>
     <entry key='notificator.sms.manager.class'>org.traccar.sms.HttpSmsClient</entry>
     <entry key='sms.http.url'>https://gateway.sms77.io/api/sms</entry>
     <entry key='sms.http.template'>p=myapifromsms77.io&from=mytelefon&to={phone}&text={message}</entry>

or

<entry key='notificator.types'>web,mail,sms</entry>
<entry key='notificator.sms.manager.class'>org.traccar.sms.HttpSmsClient</entry>
<entry key='sms.http.url'>https://gateway.sms77.io</entry>
<entry key='sms.http.user'>[Use one of your sms77 API keys]</entry>
<entry key='sms.http.password'>[Use the corresponding API secret for the API key]</entry>
<entry key='sms.http.template'>
     {
         "to": "{phone}",
         "text": "{message}"
     }
</entry>

Many Thanks
Best regards
Guido Bonewitz Raband

First option looks reasonable, but do they actually support POST with body parameters? In the API I see that they show query parameters.