Why does my speech sound 'Russianized' to my relatives?

I’m a heritage speaker and I’ve been trying to reclaim my Ukrainian, but every time I visit my family in Lviv, they point out that my vocabulary uses Russian-influenced loanwords instead of the authentic Ukrainian equivalents. I want to sound more natural and less like I’m translating from Russian in my head. Does anyone know of a good way to practice avoiding these regional traps if I don't have time for a full immersion course?