Hello,
Here is a reply I received from the support team today. The issue has now been resolved and my devices all work today:
We found that this issue was caused by corrupted database update. We have addressed the issue.
If you have not already uninstalled and reinstalled the Malwarebytes app on your device, please do so.
Afterwards, go to the device Settings > General tab > Apps > Malwarebytes Anti-Malware and tap the Clear Data button.
Reboot the device.
Next, launch the app and perform a manual update. Go to the setting screen and tap Settings > Other. Tap on the Force Update option.