Preapproval with a per diem income?

[Michael Mackney]

Hey BP community. I am a dentist (first year in the real world) and am on a production-based salary. I went to get preapproved by a lender for my first investment property and she stated that I need at least one year of income with a  per diem salary before I can be pre-approved. Is this a common occurrence with commission/production-based jobs? And what other routes are possible instead of waiting for a year. Let me know, thanks!