NodeRSA is not generate correct encrypted string for decrypt by RSACryptoServiceProvider C#

Question

My task is to encrypt data in frontend(reactJS) and decrypt it in the backend (.net core 2.0). I am using NodeRSA library in fronted and RSACryptoServiceProvider in the backend.

Front end

1. I generated two Keys(public and private).
2. Save both keys.
3. Then I import those keys and call to encrypt and decrypt methods in NodeRSA module.
4. Perfectly work both ways.

Backend

1. Generated two keys.

2. Keep it.

3. Use them and call to encrypt and decrypt methods in RSACryptoServiceProvider.

4. Awesome.

Then I use the public key which created by the frontend and generates the encrypted string. then I pass it to the backend and try to decrypt. but I got the error "The parameter is incorrect" But when I used frontend public and private keys for encrypting and decrypt methods in the backend. those keys are working fine.

This is how I am trying

Frontend (reactJS)

 const key_public = new NodeRSA({ b: 1024 }); 
 key_public.importKey(public_key);
 let encryptedText = key_public.encrypt(this.state.secret, 'base64');
 console.log(encryptedText);

Backend (.net core 2.0)

    public string DecryptFromMyKey(string crypherText)
    {
        var dataBytes = Convert.FromBase64String(crypherText.Replace(" ", "+"));
        string privateXmlString = "<?xml version=\"1.0\" encoding=\"utf-16\"?>....";
        RSACryptoServiceProviderExtensions.FromXmlString(csp, privateXmlString);
        var plainText = csp.Decrypt(dataBytes, false);
        var final = Encoding.Unicode.GetString(plainText);
        //string myKey = ExportPublicKeyToPEMFormat(csp, publicXmlString);
        return final;
    }

I check my keys and encrypted values with this site. https://8gwifi.org/rsafunctions.jsp. according to this site, my backend methods are doing their jobs correctly. It shows the correct plain text. but when I try it the encrypted text which created by the frontend. It not work.

Have I missed any coding part here? Is there any algorithm to add for frontend code?