Changing the position of the seat is the most direct method. If it is difficult to change it at will under normal circumstances, you can use some wooden boards as space, or put a low cabinet behind the seat to form a backer.
In addition, in office geomantic omen, I am most afraid that there is a long corridor behind the seat, and people often come and go, which will not only affect my work mood, but also make people who work here unlucky, easy to cause trouble and affect their careers.