How to know the customization(configuration) chages done by username?

Hello Experts

i have a problem in development , one configuration was changed, but i would like know about that config change

by which user id , i do not have hte customization request number.

that DEFINE TOLERANCE GROUP FOR EMPLOYEE IN SPRO. if their is any changes in that config.

for ex. amount has changed, how to see the cahnge log , those details like changed by or CR(customization request)

Thanks