Landlord Vision

I have recently bought my first buy to let property. I have been experiencing with the tax report function in Landlord Vision. I am finding that even when my gross income from rent is less than £1,000 the calculation shows that I owe tax if my income from other sources (which I assume includes salary from a job) is over the 40% threshold. Is the £1,000 tax free “property allowance” only applicable to people earning below the 40% threshold from wages?