As a disciple who was not very prominent in the sect, Zhang Yi was not required to do missions as he did in the other sects, but if he did not do the missions he could not get cultivation resources.
The reason was that Zhang Yi reached the Soul Birth realm without using the sect's resources, and so Sword Sect had no right to ask Zhang Yi to do missions without receiving anything from the sect.
In the past he had to do the missions because he received special attention from the sect, besides, Zhang Yi himself always looked for missions to gain more experience and thus be able to advance his cultivation.
This time he needed no experience or cultivation resources, so he would remain discreet for the first few years until he had time to communicate with elder Lu Bi, while he could concentrate on his cultivation to try to reach the realm from Soul Refinement.