The best option is to go to the support page for your laptop on the Dell website to download and install (not update) the version of chipset drivers and Touchpad drivers they provide for your laptop model.
If that does not resolve the problem, open the Settings app, go to Windows Updates - Installed Updates, if there was an update installed last night, that may have caused the problem the best option may be to uninstall that update to test if that resolves the problems with the touchpad.