Purchase lending restrictions with using rental income

[Mehgan Moore]

I am trying to qualify for another multiplex and have been told we can not use the rental income from the other units to qualify...? We currently live in one of our multiplexes and are looking to rent out the unit we live in and move into another unit within a new multiplex. Lender is saying we can not use the rent amt for the other unit located in the new purchase (currently rented for $2100 a month) to qualify. Is this a real thing? Lender said they would use that income to do a cash out refi but not for a purchase...? Odd to me.