When you get your short term answer settled, think of the long-term preventative maintenance.
Every 3 or 4 months, fill the sink to the brim with hot water, and then let it all drain. The heat and pressure will help melt lipid deposits and flush them down the system.
do this with all the sinks nearby as well, drain lines like to restrict and regular flushing can help prevent a lot of headache.
I sometimes pour a kettle of boiling water down the kitchen drain to melt the fats. I recall seeing a youtube video of a guy boiling pvc fittings to separate them and reuse them, which caused some concern for my habit of pouring boiling water down. But he had to boil those fittings in a pot for like 30 min with all sides of the fitting getting heat, so I’m not worried.
Budget permitting, it’s best to pour the hot water down ~15-20 min before going to bed, then just before going to bed pour ~50—100ml of enzymes. Enzyme-based maintenence cleaning is most effective when the sludge they will consume is warm. Let the enzymes feast on the nasties all night long.