Trunks are sometimes making noise

HI

I have 4 trunks co line and two ip lines

What happens is that my 6 trunks are not acessible and when i tried to reach from outside it keeps on ringing.
So if that happen at nigth or on the wwekend my 24 hrs service transfert to the pagette is no longer working.
Is there a way that in the event the trunks are not working that the system would reset it self .

Thanks