Error: Unknown type name 'TLSSocket'; did you mean 'TCPSocket'?

I get this error: Error: Unknown type name 'TLSSocket'; did you mean 'TCPSocket'? in "main.cpp", Line: 16, Col: 5 when I run try to open a `TLSSocket socket;` instead of a `TCPSocket socket;` for a secure connection with my MQTT broker. Any ideas how to fix this?
