Unable to see clients - GET /server.pem HTTP/1.1" 404

Hi

I'm wondering why I get this issue when the different clients, windows and ubuntu 19.04 are able to make the the following request and get a 200 ok response:
request:
http://myserver:8080/api/users/me/notifications/pending/count
response body:
{ " count":0}

But the more important step when setting up the client does not work:
EBUG:2019-12-06 06:55:47,702 connectionpool:437] http://myserver:8080 "GET /server.pem HTTP/1.1" 404 232

Is my server supposed to have a file named "server.pem" somewhere? I searched the whole computer and this file does not exist.

Regards,
T