LattePanda UPS burnt my LattePanda Delta

I connected the LattePanda UPS to my LattePanda Delta today. After attempting to upload HID Power Device and DFROBOT LUPS, I connected a USB-C charger to the UPS's USB-C jack (with batteries installed). Subsequently, the LattePanda Delta emitted sparks and burned. Could this issue be related to an Arduino upload error, or might it involve a defective UPS or LattePanda unit? I used my laptop's charger, which outputs 3A at various voltages (5V, 12V, 15V, 20V). I've ordered a replacement but would appreciate any advice to prevent a recurrence.