SoapUI request with SSL certificate (Error getting response; javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?)

Question

I have a project on Java+Spring. And there is a sertificate storage (.jks file). I set up this .jks file in my project. Now I want to make a request with the SoapUI 5.5.0 using SSL.

I opened SoapUI -> File -> New Rest Project -> insert url (https://localhost:8080/my-endpoint-01) and click OK -> then gave to soapUI-project new name "Spring Security"

Then I went to configure the SSL certificate: File -> Preferences -> SSL Settings:

• Keystore: path to the storage of the keys .jks
• Keystore Password: password

Also in the working area of the SoapUI, at the bottom left there is a section "Request Properties". There is a "SSL Keystore" item here. I also selected my certificate store here:

Then I want to test with https request:

https://localhost:8080/my-endpoint-01

but I got an error: "Error getting response; javax.net.ssl.SSLException: Unrecognized SSL message, plaintext connection?":

Can you explain to me, please, what I am doing wrong?