This definitely works for my 2020
VXDAS Auto Tire Pressure Monitor Sensor TPMS Relearn Reset Activation Tool OEC-T5 for GM Series Vehicle https://www.amazon.com/dp/B072BK693N/ref=cm_sw_r_cp_apip_cSe8njXY2tQlY
this looks like it might work
VXDAS TPMS Relearn Tool for GM Tire Sensor TPMS Reset Tool Tire Pressure Monitor System Activation Tool OEC-T5 for GM Buick/Chevy/Cadillac Series Vehicles 2021 Edition https://www.amazon.com/dp/B072BK693N/ref=cm_sw_r_awdo_navT_g_MT788VY02CMDGQZ4CJTS
$10 works perfectly everytime. https://www.amazon.com/dp/B072BK693N/ref=cm_sw_r_cp_apa_i_SAJwFbCKYN74Y
My experience is that most people having issue are holding it to the stem. Hold it to the tire just under the stem. This is because the transmitter is on the end of the stem inside the tire not outside.
BTW Amazon sells the OEM sensors for way way cheaper than the dealership or tire shop. I bought these and had them install them when the tires were mounted. They were charging $45 per TPMS for these. Amazon sells for $17 the exact OEM part. https://www.amazon.com/dp/B072BK693N/ref=cm_sw_r_cp_apa_i_SAJwFbCKYN74Y
It's really easy to fix, its basically a 10 dollar tool on Amazon (https://www.amazon.com/VXDAS-EL-50448-Pressure-Monitor-Activation/dp/B072BK693N) this one worked perfectly for me.
You need that or to go to a tire shop/auto shop. Process takes less than 1 minute.