Problem of convergence and cross section value for Bhabha scattering

Juergen Reuter suggests this article as an answer to your question:
FAQ #3404: “Why does Whizard give a much larger cross section than other generators?”.

Dear Yehia,
this is actually a recurring question for which we created a FAQ now (cf. the link). Whizard doesn't set any default cuts, so you need to set a minimal angular cut here or a cut on the momentum transfer for the t-channel contribution. Other generators normally set a default minimal pT for final-state leptons which would affect Bhabha scattering as in your example as well.
Cheers,
    JRR (Juergen)

Thank you Juergen.

I think the cuts are not the main reason for this since the difference orders of magnitude higher. In madgrap I get a cross section of O(10^5) fb while in whizard I get O(10^16) fb with an error of O(10^16)!.Even after I applied cuts on pt and eta in the sindarin file.

Using this cut
cuts = all M < -10 GeV [incoming e1:E1,e1:E1]
on the momentum transfer between incoming and outgoing electrons/positrons, and then I get (with beam spectrum and ISR)
a perfectly converging integration of the right order of magnitude:
| VAMP: parameter mismatch, discarding grid file 'DY.m1.vg'
   1 1000 2.7341512E+06 3.62E+05 13.25 4.19* 4.11
   2 998 2.6873194E+06 1.23E+05 4.56 1.44* 11.44
   3 996 2.8615803E+06 5.99E+04 2.09 0.66* 25.26
|-----------------------------------------------------------------------------|
   3 2994 2.8259557E+06 5.33E+04 1.88 1.03 25.26 0.85 3
|-----------------------------------------------------------------------------|
   4 9997 2.7911859E+06 1.86E+04 0.67 0.67 20.97
   5 9997 2.7432835E+06 1.84E+04 0.67 0.67 20.37
   6 9997 2.7925499E+06 1.91E+04 0.68 0.68 13.08
|-----------------------------------------------------------------------------|
   6 29991 2.7750988E+06 1.08E+04 0.39 0.67 13.08 2.29 3
|=============================================================================

Thank you this solved my problem.