The usage of at is the error
Step-by-step explanation:
IN is for large spaces that can enclose (village, city, state, province, country, continent, mountain range, desert, zone, etc.)
ON is for surfaces.( street/avenue/road, most bodies of water, etc)
AT is for points ( We live at an address, at a certain point and at a certain person’s residence if just the possessive case is used to mean the residence.)
Examples:
1- I live in Belgrade.
2-They live on Mulberry Street
3-I live at 199 Main Street
Conclusion: AT is a tiny point, ON is bigger, and IN is big enough to surround you.