Error while connecting via Power Automate "Private key file could not be parsed"

I keep getting the same error when trying to create a connection to document services. What am I doing wrong? I base64 encoded the file I retreived at signing up. This one: 

{
"project": {
"id": "4566206088345033186",
"name": "Fullapikey",
"title": "Full api key",
"description": "PDF Services",
"org": {
"id": "1347161",
"name": "chargecars-gmail.com",
"ims_org_id": "84681EAE64D7F8C40A495C53@AdobeOrg"
},
"workspace": {
"id": "4566206088345041923",
"name": "Production",
"title": "Full api key",
"description": "PDF Services",
"action_url": "https://1347161-fullapikey.adobeioruntime.net",
"app_url": "https://1347161-fullapikey.adobeio-static.net",
"details": {
"credentials": [
{
"id": "491054",
"name": "Full api key",
"integration_type": "oauth_server_to_server",
"oauth_server_to_server": {
"client_id": "1bb7a0af46ac4711a0480f0738b744d5",
"client_secrets": [
"p8e-2VwC6gUq944Tco4TKY3AHtmpd8n8L9Lc"
],
"technical_account_email": "2c47eefb-5fb7-40f4-a151-5bae949970a7@techacct.adobe.com",
"technical_account_id": "87CC1EBC64D7F8F50A495E34@techacct.adobe.com",
"scopes": [
"openid",
"AdobeID",
"DCAPI"
]
}
}
],
"services": [
{
"code": "DocCloudSDK",
"name": "PDF Services API"
}
],
"runtime": {
"namespaces": []
},
"events": {
"registrations": []
}
}
}
}
}

Is that the right way to do it?