If you’re using the Electra1131 jailbreak on your iOS 11.2-11.3.1 device, then you may want to consider opening Cydia and installing the newest updates to Substitute and Tweak Injector as soon as you humanly can.
These updates, which were issued by the Electra Team on Friday, implement an official ‘Safe Mode’ on devices that have been pwned with the Electra1131 jailbreak tool.