If at first you don't succeed, read the instructions.
If they did not come with this model I am sure you can go online and find out all about how the esc's work. YOU took it apart, now YOU need to fix it. You are sitting in front of the greatest research tool that has ever been developed yet you are asking questions hoping someone will solve your problems but just do the research, find the solution and fix it yourself. That is the satisfying part of this hobby. You may not like to build so you buy a model pre-built but sooner or later you have to work on them so learn how. Just my opinion but I cannot imagine having a model and not knowing how to work on it. That would be no fun!!