incremenal dynamic analysis problem

[KSH]

Hello
I'm a student.I got some problems when I did incremenal dynamic analysis of 1-Story reinforced concrete portal frame with and without viscous dampers by OpenSees software somedays ago.
When peak ground acceleration was 0.85 g ,it could not work,and the analysis was failed.
The warning is:
WARNING: CTestNormDispIncr::test() - failed to converge
after: 10 iterations current Norm: 6.26866e-012 (max: 1e-012, Norm deltaR: 1.3512e-006)
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 15.92
OpenSees > analyze failed, returned: -3 error flag
regular newton failed .. lets try an initail stiffness for this step
WARNING: CTestNormDispIncr::test() - failed to converge
after: 100 iterations current Norm: 0.0047792 (max: 1e-012, Norm deltaR: 2881.31)
ModifiedNewton::solveCurrentStep() -the ConvergenceTest object failed in test()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 15.92
OpenSees > analyze failed, returned: -3 error flag
Transient analysis completed FAILED
I just donnot know how to let my program work again.If you have some advices or opinions,please contact me and thanks a lot.