Tell your players to give you the crash address(es) so that you can understand where the issue comes from.
When you get the crash address, simple search for it here:
https://sampforum.blast.hk/showthread.php?tid=339691
Search for familiar addresses to the one(s) your players send you, as it may have a difference in the last two digits but still mean the same.
You might also want to create a file named "pawn.cfg" and write "-d3" in it, and include crashdetect. Don't forget to run the plugin as well, you can get it from here
https://github.com/Zeex/samp-plugin-crashdetect
Compile your script and start, it should report any problems in your code.
There may be two common factors of crash if your players don't crash when doing specific stuff but just randomly:
1. You are exceeding the maximum objects displayed in one place (1000 for 0.3.7) and (2000 for 0.3.DL), if you do, and players reach that place, they'll crash.
2. You are creating an invalid object ID, that will make players crash at that object's coordinates (when streamed).
3. You mentioned the problem happens when you teleport to someone, it can be the client crashing due to loading too many objects having the ones in the older position still streamed.
If the problem happens when you do some stuff, debug them and you'll reach the problem easily. You should have a test server to try and debug the problem with someone else.