The remote certificate is invalid according to the validation procedure: RemoteCertificateNameMismatch, RemoteCertificateChainErrors

We are migrating our worker service from .NET 4.5 to .NET 5 (latest version).

We have created a Connected Service but when we try to Invoke method we are getting error in terms of Invalid SSL connection. In our old code we used

ServicePointManager.ServerCertificateValidationCallback = (sender, certificate, chain, sslPolicyErrors) => true;

but that is not helping us right now. We can not use HttpClientHandler solution cause our app is Console App configured as a service and we are using Generated methods from Connected Service.

For example

TransportPortTypeClient trans = new TransportPortTypeClient(TransportPortTypeClient.EndpointConfiguration.SecureSOAP12Endpoint);

var ws_docoments = await trans.select_xxmob_dokumenti_transport_operationAsync(start_date));

Error that we are getting is "Could not establish trust relationship for the SSL/TLS secure channel with authority 'site,com:443'."

Old code (.net 4.5) and SoapUI on same machine works fine