1. How to set default location to my city , Now default location at Germany.
please see at url: khonkaen.agency/item/new

2. in this Post page :: khonkaen.agency/item/new
i set the location on the map and public, when i see on item page location it wrong. How to fix it? (you can test at khonkaen.agency/item/new)

@ipreaw
1) user can enable location detection, that is done using HTML5 geolocation (prompted in browser)
2) when user select location from map, coordinates of this location are sent to database, then these coordinates are used to show listing on map. You can check coordinates in t_item_location table.