Update php ini file on Elastic Beanstalk

Hello, i deployed REDCap with the cloudformation template from Vanderbilt University [https://github.com/vanderbilt-redcap/redcap-aws-cloudformation]. Issue i have is not able to upload file exceed more than 2M. i have to update the php.ini file so to increase some paramters like max_execution_time, max_file_uploads,max_file_size etc ..... i tried to dowload the zip file of the version of the application and then in the .ebxtensions directory add a config file but every time i re-deployed this my beanstalk crashed and revert back to the old version. Below is my custom config file files: "/etc/php.d/project.ini" : mode: "000644" owner: root group: root content: | upload_max_filesize=64M post_max_size=64M

Is there any step i missed ? Thanks