Maybe check that you are not using a different JRE or JDK for running Servoy then then one you added the certificate to. You are using a self-signed certificate right?
So the cacerts file that you modified should be the one from [your_JRE_path]/lib/security (or if you use JDK it’s [your_JDK_path]/jre/lib/security) folder of the JRE that you run Servoy with.
You can check the contents of cacerts using something like - of course after changing [your_JRE_path] to your real path: (this is for windows and it writes output in 1.txt file, for Mac/Linux you need to change it to match shell syntax)
keytool -list -v -keystore "[your_JRE_path]/lib/security/cacerts" 1>1.txt
The default password is “changeit” - it will ask for the password.