Total Stress Analysis-CTestNormDispIncr-failed to converge

[AnnaKowal]

Hello,

I haven't been used OpenSees for a long time and would appreciate some experienced users advice.
I am trying to run Total Stress Analysis of a Layered Soil Column (Total Stress Analysis).
Currently using a simplest script (freeFieldSingle.tcl) from the website example for verification. It works fine for the example file, however keep failing for my velocity time history file.

I updated motionDT = 0.01 (its 0.005 in the example) and number of steps in ground motion record = 10240 (it's 7990 in the example).

I got warning on Dynamic Analysis:
WARNING: CTestNormDispIncr::test() - failed to converge
after: 15 iterations current Norm: 0.0741508 (max: 0.001, Norm deltaR: 351.17)
NewtnRaphson::solveCurrentStep() -the ConvergenceTest object failed in test()
DirectIntegrationAnalysis::analyze() - the Algorithm failed at time 19.55
OpenSees > analyze failed, returned: -3 error flag
Finished with dynamic analysis...

my analysis definition is: # analysis objects
constraints Transformation
test NormDispIncr 1e-3 15 1
algorithm Newton
numberer RCM
system ProfileSPD
integrator Newmark $gamma $beta
rayleigh $a0 $a1 0.0 0.0
analysis Transient

analyze $nSteps $dT

I would be really grateful for your suggestion and ideas what I should look at and how to fix that issue.