Area - Code Sining. When attempting to sign ClickOnce manifests while publishing an application, it throws an error. How to solve the problem?

Question

Electronic digital signature

A company (software developer) has acquired a software code signing certificate.
We tried to sign an exe-file using the SignTool utility with this key, and the signing was successful.
Applications are published using ClickOnce technology. However, when trying to sign the ClickOnce manifests while publishing the application, it gives the following error: "An error occurred while signing: Only certificates that use RSA encryption are valid for signing ClickOnce manifests."
There have been attempts to manually sign the manifest file through the Visual Studio command line. The following request was entered:
mage -sign "path to the .exe.manifest file" -CertFile "path to the pfx certificate with private key" -Password "pfx password"
This request gives an error:
This certificate does not contain the private key "path to pfx certificate with private key". If it is a public key certificate, provide valid CSP and key container names.
Please tell me how to solve this problem.