Variable substitution on curl command

Question

I'm just starting with bash scripting and trying to replace variables within a curl command, but can't figure it out.

#!bin/bash
bucketName='temp-sigurl-temp' 

remotePath='folder2/subfolder22/file.wav' 

localPath='temp.json' 

remotePath='folder2/subfolder22/file.wav'

uploadUrl=$(curl -m 70 -X POST https://us-central1-gcp-project.cloudfunctions.net/function_name -H "Authorization:bearer $(gcloud auth print-identity-token)" -H "Content-Type:application/json" -d '{"BUCKET_NAME":"$(bucketName)", "REMOTE_FILE_PATH":"$(remotePath)", "BLOB_TYPE":"audio/wav"}')

echo "Upload Url : $uploadUrl"

This is the error I get, Could not handle the request Thanks!