tie up

verb
  1. 1

    To secure with rope, string, etc.

    โ€œDon't forget to tie up your hair before you bake.โ€

  2. 2

    To occupy, detain, keep busy, or delay.

    โ€œHe has been tying up the phone lines for hours now.โ€

  3. 3

    To complete, finish, or resolve.

    โ€œI'd like to tie up the project before I leave.โ€

Source: https://en.wiktionary.org/wiki/tie%20up