D130 shows pri_find_dchan span 1 d-channel is down

I have two PRI cards both of D130 and D230 both configured correctly show no-error but as well as dahdi show status show ok and pri show spans show up & active but when incoming calls it "pri_find_dchan span 1 d-channel is down" and disconnect the call

Hi
Please contact my skype：Dario.hu2 and prepare teamview for remote help.