I have an error that says
The estimation algorithm did not converge after 50 iterations and the forecast was not done.
What can I do to prevent this error? Like how can I check the data before forecasting?
In general, if an ARIMA estimation does not converge, it is likely that the model was not a good fit for the data. However, you can increase the number of iterations by adding the argument MAXITER=200, for example.
Did you try to identify a model? Or did you simply assume a model? Convergence depends on starting values, number of iterations AND the size of the numbers being analyzed. Try scaling your data.