Let me take a few minutes to talk about the mysterious 2TB limit. In fact, in a word, it is due to the type of initialization performed on the disk. Your disk is MBR type! The MBR supports up to 2TB per single partition. So you can only see and use 2TB in your computer. How To Solve The Problem?
Now that you have known 2TB is the max volume in a MBR disk. I also want to tell you that there are two types of disk, another is called GPT(GUID Partition Table), a new partition/disk style, which support bigger than 2TB. So the solution is converting MBR to GPT? Yes, it is!
At first, verify that your computer equipped with UEFI if your system partition is in the pre MBR disk. The UEFI will show up in the bios. Second, it is about operating system requirements. You can consult the chart below.