What are the Settings for both Tracks in the Scale menu (FUNC + PAGE)?
Check the CH.LEN and M.LEN settings.
CH.LEN (Change Length) controls for how long the active pattern plays before a cued or chained pattern begins to play. This setting is important when, for example, you set M.LEN to INF. If you do not make any CH.LEN setting, the pattern plays infinitely, and the next pattern is thus not cued. By default a cued pattern change happens at the end of the pattern (CH.LEN set to OFF).
M.LEN (Master Length) controls the number of steps the pattern plays before all tracks restart. An INF setting makes the tracks of the pattern loop infinitely, without ever being restarted. Note that this setting also affects for how long the active pattern plays before a chained pattern starts playing. The CH.LEN parameter overrides this if its parameter value is less than the M.LEN value.