@Yasmina > Back at rekordbox v2, a license was required to unlock the software; the base version of rekordbox was a paid product. As of v3, it was made available for free.
rekordbox 4 continued to be free to operate in a similar manner to all prior versions (to organize music, edit hot cues, memory points, beat grids, tags, link to players, etc.), however with the addition in rekordbox 4 and 5 of the PERFORMANCE MODE (known as "rekordbox dj"), a paid add-on for allowing DJs to use the software to perform directly within the software, this does require a rekordbox dj license, not the old rekordbox 2 license.
Unfortunately the license that came with your XDJ-R1 is not valid for rekordbox dj, and in order to use the performance mode, you must purchase either a full license or a monthly subscription. Without this, you can still continue to use rekordbox in export mode for free to do the same things you were doing with previous rekordbox versions.