Communicate with Topdesk API

Hi all. I am using powershell to communicate with the Topdesk API, which seems to run fine. I use a JSON string to send data to the API. In that JSON there is a request field with a long text in it, I have used \n on various places to get newlines in the text. But when I open my generated incident in Topdesk there are no newlines. When I retrieve my data via the Topdesk API the newlines are also gone. So, how do I escape these newlines correctly so that TopDesk recognizes them?

Not really a PowerShell problem. Some suggestions to try:

\\n
\r\n
\\r\\n
\n
\r\n