Getting Bad Substitution while running Bamboo plan

[Deepal Neema]

error	22-Feb-2021 17:01:03	/home/bamboo/agent1-home/xml-data/build-dir/IOT-IOT7-JOB1/iot-infrastructure/bamboo-scripts/bamboo_build_and_stage_python_template.sh: line 2: ${bamboo.build.working.directory}: bad substitution

On all the Bamboo variable we are getting bad substitution. Below are my file starting two lines

echo 'Bamboo agentId......'
echo 'Bamboo working directory is......' ${bamboo.build.working.directory}