Assuming your 5th partition, "LENOVO_PART" is also primary partition (hidden by error message box in screen shot), and I'm sure it is the case.
The problem is any disk can't have more than 4 primary partitions, and you already have 4.
What you need to do, is first convert any contiguous(C: or D: ) partition to unallocated space to logical, then create as many sub-partitions in that logical partitions.