BURG.L is a friendly and helpful robot that you can find in the Oak Tree Lab in Grounded. When you find him, he will give you daily challenges that you can complete to earn Raw Science, which you can then use to buy plans for better bases from him. Some players have been running into an issue with the game, however.
If you accidental hit BURG.L with a tool or weapon, he may not be in the lab the next time you visit. BURG.L has been disappearing on some players who have accidental hit the little guy, and he doesn’t seem to want to come back.
Unfortunately, the only thing you can do right now is go back to an earlier save, or start a new game. The game should be constantly making Autosave files for you, so there should be something in your save history that will bring you back to a time before BURG.L abandoned you.
With early access games like Grounded, it is always a good idea to regularly save your game, as you never know when you might run into a serious bug like this one that can end up ruining all the playtime that you have put into the game up until them.
While developer Obsidian is almost certainly aware of the issue and can stop the little robot from running away should players accidentally hit him, whether or not they can retroactively fix the problem for players who have already encountered it remains to be seen. As such, make sure you save regularly so that you have plenty of save files to choose from should something go wrong, and do your best not to hit BURG.L.