diff --git a/lua/import-cost/extmark.lua b/lua/import-cost/extmark.lua
index 0e2c2b3..7929420 100644
--- a/lua/import-cost/extmark.lua
+++ b/lua/import-cost/extmark.lua
@@ -73,9 +73,9 @@ function M.delete_extmarks(bufnr)
             == util.normalize_string(
                 vim.api.nvim_buf_get_text(
                     bufnr,
-                    data.line,
+                    data.line - 1,
                     0,
-                    data.line,
+                    data.line - 1,
                     -1,
                     {}
                 )[1]