A 403 Forbidden error is a webserver’s code for:
"You’re not allowed here."
Is the error specific to you - or is it the same for everyone everywhere? Don't assume it's everyone everywhere just because two of your coworkers also get the error. Your coworkers likely share the exact same IP address as you! Try the same URL from your cell phone (not on wifi) or visit https://www.downforeveryoneorjustme.com and type in your desired URL to find out for sure.
You may have been mistakenly blocked by a security measure that keeps the website safe from Hacker’s bots.
This is an issue with the webserver and only the administrator of the website or it's server will be able to resolve it.