GET request to Patch Management API (Patch Manager Plus - Cloud)

I followed the instructions in the Patch Manager Plus - Cloud (https://www.manageengine.com/patch-management/api/) . And then get information (like refresh_token, client_id, client_secret), get access_token for every hour.

When trying to initiate a GET request to api/1.3/som/computers, I get the following response back.

{
"message_response": "Unable to retrieve details, Please try again later.",
"error_code": 90004,
"error": "invalid input found",
"message_version": "1.0",
"status": "error"
}

My code is as follows:

axios.get('https://patch.manageengine.com/api/1.3/som/computers', {
headers: {
"Authorization": << access_token >>
}
})

I think there is a problem with the header such as missing some parameters. (I tried running the api in the browser (logged in) and got the data). I also searched but couldn't find a description for this part.

Can anybody help me, please?