Kernel flash may cause issues in Magisk. It’s experimental. Please try installing this separately in Magisk. https://image-nethunter.kali.org/nethunter-installer/kali-2025.1/kali-nethunter-2025.1-generic-amd64-full.zip
Check if everything is stable.
And try install kernel straight from NH app kernel tab. If will offer available kernel. If that cause issues too, try installing kernel in twrp kernel-nethunter-20250310_235658-oneplus8-oos-eleven.zip · main · yesimxev / kali-nethunter-kernels · GitLab