If you desperately need to connect a 12V LED strip to a 24V system, see how you can accomplish this using a simple electronics principle.
LED Light Strip Dimmer, DC 12V-24V 30A PWM Dimming Controller for Dimmer Knob Adjust Brightness ON/Off Switch with Aluminum Housing, Single Channel for 5050 3538 5630 Single Color Light Ribbon
12V Interior LED Light Bar, 108 LEDs Strip Lights 1800LM 6W DC 12V LED Light Strip with Switch for Car Truck Bed Van RV Cargo Boat Cabinet Enclosed Trailer Lights Fixture
Used for all SUPERNIGHT RGB LED controller Enhancing RGB signal for RGB LED strip lights more than 32ft Extending LED strip lights and keep the RGB
SUPERNIGHT DC 12V to 24V 12A LED Strip Lights 3 Channels RGB Signal Amplifier Repeater for 10m 4 Pin 5050 3528 LED String Lights - 2 Pieces Pack
HitLights LED Strip Lights Cool White 5000K, 16.4ft High Density 12V Tape Light, UL-Listed, 600 LEDs, 300Lm/ft, Flexible Dimmable Rope Lights for Bedroom, Kitchen, Cabinet (Power Source Not Included) : Tools
UL-Listed 24V Commercial Grade LED Strip, 3528 120/ M Med-Output
Using a 12V LED Strip in a 24V System
Hi! I would like to connect my LED lights (Vaxmyra from IKEA) designed for 24V system into my 12V system, do I need a current limiting resistor? - Electrical Engineering Stack Exchange
Ustarus White LED Strip Lights Dimmable 26ft 24V 3000K-6500K LED Tape Rope Light with Remote Flexible 2835 LED Ribbon for Kitchen Under Cabinet Bedroom Mirror Indoor Home Daylight Warm White
12-volt vs 24-volt LED tapes recommended voltage & wattage