unreliable
US /ˌʌn.rɪˈlaɪə.bəl/
UK /ˌʌn.rɪˈlaɪə.bəl/

1.
poco fiable, no fiable
not able to be relied upon; not dependable
:
•
The old car was very unreliable, often breaking down.
El coche viejo era muy poco fiable, a menudo se averiaba.
•
His information is often unreliable, so double-check everything.
Su información es a menudo poco fiable, así que verifica todo dos veces.