@samisamixp I'm not sure you are sending the correct openssl command.
Blynk server GitHub states:
Generate own SSL certificates
Generate self-signed certificate and key
openssl req -x509 -nodes -days 1825 -newkey rsa:2048 -keyout server.key -out server.crt
Convert server.key to PKCS#8 private key file in PEM format
openssl pkcs8 -topk8 -inform PEM -outform PEM -in server.key -out server.pem
If you connect hardware with USB script you have to provide an option '-s' pointing to "common name" (hostname) you did specified during certificate generation.
As an output you'll retrieve server.crt and server.pem files that you need to provide for server.ssl properties.