AccountID handles errors by recursing, so you might just be building up a massive call stack. You should write your code with use warnings; like Eily suggests, so you would get a message about that. Try putting a debugging print in there to see if it's fetching the same account over and over again.

sub AccountID{
  my $accountId=shift;
  print "Fetching account $accountId\n";
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If it turns out that's what is happening, you need to find a better way to handle failures. Don't just keep retrying them over and over again forever!