The neglect of those who served in the Temple led to a severe crisis in its daily operations. Nehemiah discovered that the financial support system meant to sustain the Levites had completely collapsed, forcing them to abandon their holy duties simply to survive. He learned that the specific portions and tithes God commanded the people to provide for the Levites [אבן עזרא, מלבי״ם] had stopped arriving at the Temple altogether [רש״י, ביאור שטיינזלץ].
Without this vital support, the Temple workers found themselves entirely without an income. As a result, they abandoned their holy shifts and scattered to the fields. Commentators offer two distinct explanations for this departure. One approach suggests that the Levites had no choice but to return to physical labor, plowing and harvesting their own land just to secure enough food to stay alive [מצודת דוד, ביאור שטיינזלץ]. Another perspective argues that they went out into the agricultural fields and threshing floors to actively track down the people and demand the gifts that were rightfully owed to them [רש״י, רלב״ג].
Ultimately, this mass departure affected the entire workforce of the Temple. It included all the dedicated servants whose essential roles kept the sanctuary functioning, specifically those who sang the sacred music and those responsible for closing the Temple gates [מצודת דוד].