Do it again and make extra sure you get the make settings correct:
I just tried with my old SKR 1.4T and it works flawlessly.
A properly flashed Klipper serial for a SKR 1.4T needs to look like:
klipper@bigtreetech-cb1:~/klipper$ ls /dev/serial/by-id/*
/dev/serial/by-id/usb-Klipper_lpc1769_0C70001625813AAF86E06B5CC32000F5-if00
klipper@bigtreetech-cb1:~/klipper$
Follow the dmesg instruction and post the resulting file.