You finally got all your requirements from all your stakeholders, but it's a lot of information and you need to be able to be more concrete about them. Basically, you have to evaluate what people told you. Well, let's start with inconsistencies you might have. There are also different types of inconsistencies. You can have a terminology clash, where you can have two or more different terms that refer to the same thing; or you can can have a designation clash, which is when one term refers to different things. A terminology clash could be when you call what you sell product and item; they both refer the same thing and you might be using these terms interchangeably, causing confusion. A designation clash could be when you use the word user while having more than two types of users.
You can also have strong or weak clashes between your requirements. A strong conflict is when two requirements completely contradict each other. This is as simple as somebody saying that something can be done and another one saying it cannot be done. When you get into weak clashes, things get more interesting. This is basically when two or more requirements cannot be satisfied under a certain boundary condition. Terminology and designation clashes are easy to resolve, just keep a glossary of terms to make sure that communication is effective. When it comes to strong and weak clashes, you need to communicate and resolve with stakeholders. This is when you are going to firstly, identify all of the overlapping statements. Then, verify which combinations generate conflicts among them and then document them in order to organize them. Afterwards, brainstorm conflict solutions in order to present to the owners of the conflicting requirements. Finally, evaluate them and present them. The final solution will come from your stakeholders because, of course, they are the ones who envision the final product.