Hi Sandeep, maybe do you need a API key, see Authentication | Mendix Documentation
Most Mendix Platform APIs require their users to authenticate themselves. This is done by using API keys.
2 Obtaining API Keys
To obtain a Mendix API key, follow the instructions in the API Keys section of Mendix Profile.
3 Using Authentication Headers
Any call to the Mendix Platform APIs should be authenticated using the following request headers:
Mendix-Username – the login name of the requesting user with the required privileges in the Mendix Platform
Mendix-ApiKey – the API key of this user