Again having problems with the RFC and taxes. I provided my RFC, it was approved and I received my first payment as normal, with only 1% discount of taxes. Now checking my invoices two pending payments are same, only 1% taxes discount but I just noticed that the last payment is taking away 20% of taxes. How can I be possible that this is happening if I already provided my RFC? I have seen that I'm not the only one having this problem.