It’s not a Get method you’ll have to use post
curl --location --request POST 'https://YourEpicor.Com/EpicorLive10/TokenResource.svc/' \
--header 'username: YourEpicorUserName' \
--header 'password: YourEpicorPassword' \
--header 'Accept: application/json'
This will responde with
{
"AccessToken": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJleHAiO_SNIP_CAUSE_H4K3RZ",
"ExpiresIn": 28800,
"TokenType": "Bearer"
}