Never use iop(5/13=1)
scf=maxcycles=125 is meaningless, since it is too close to the default 128
I don't find any reason to use CAM-B3LYP for this system.
I have a blog article to comprehensively discuss how to solve SCF unconvergence problem: http://www.shanxitv.org/61
Try these keywords instead:
# opt B3LYP/6-31g(d) em=gd3bj scrf
I'm performing optimization and frequency calculation on the below system.
It gives a convergence issue.
I have tried several options 
ex:  increasing the number of cycles.
     As we can not use qc, I have used alternative keywords; use=l506
Nothing worked. Your suggestions will be helpful.
Thanks and regards
Shen
 opt=calcfc rocam-b3lyp/6-31g(d) scrf=(iefpcm,solvent=water)
scf=maxcycles=125 iop(5/13=1)
Title Card Required
1 2
 C                  1.35656100    1.13118500   -0.07295400
 H                  1.28256500    2.07700700   -0.11348300
 C                  0.90312800   -0.99348200   -0.18842500
 H                  0.44545800   -1.81385500   -0.32705900
 N                  0.35868700    0.24094300   -0.38379100
 N                 -4.53096900    0.01670200    0.10290700
 H                 -3.92323500    0.41587700   -0.42267400
 H                 -5.30860900   -0.19732300   -0.32006000
 H                 -4.70348900    0.60048000    0.77614600
 H                 -4.14393200   -0.74142100    0.41322600
 N                  2.42986200    0.46674300    0.28898400
 N                  2.14143500   -0.89110000    0.21506800
