I have same issue today. After windows update, process that I use several years stops working.

In my case solution was:

• delete certificates folder C:\Users\{your user name}\.office-addin-dev-certs\

• download latest addin-dev-certs now is '2.0.3' I use to have '1.7.8' before

• use PowerShell as admin

• update npm i office-addin-dev-certs

• install them for 30 days (or what time you want) and I use for anyone here npx office-addin-dev-certs install --days 30 --machine

• test them npx office-addin-dev-certs verify

• and then start addin localy as common npx office-addin-debugging start manifest.local.xml desktop --app word

Hope it helps someone