Well when you ordered us the customization for invite course application addon you did not mentioned that you will be selling courses using the batches as well.
Now that I have checked your site and found that you are using wplms batches , in wplms batches the issue is when user purchases and subscribe to a course , then if there is any batch connected to the course , then user has to select to enroll into it .
Since you course has two or one batches then user has to click on the enrol now button to enroll into a batch and then he can start the course :
http://somup.com/cqjiIReFvL
SOLUTION : disable " <span style="color: #494949; font-family: Lato; font-size: 14px; font-weight: bold;">Students must be enrolled in a Symposium to pursue this course</span> " in course settings .