On most devices, you can disable app optimization for SKEDit in Settings to stop it from disabling the accessibility. This is usually found in Settings > Battery.
For example on the Samsung S5, go to Android Settings > General > Battery > look under App Optimization and select Details. Then find SKEDit and turn it off.
On other devices, you may have to specify that SKEDit should be ignored in battery optimization. For example, on Huawei phones, go to Settings > Apps > Advanced Options > Ignore Optimations and toggle "allow" for SKEDit.
If SKEDit is running on an SD card (external storage), that means it's "unavailable" when the system boots This can turn off accessibility. Try moving it back to main storage.