Called in asking for our "IT Manager" by name, but the person they asked for isn't in our IT department. I asked what they were calling in regards to due to our IT department being very large and we have multiple IT Managers. The guy seemed annoyed with me and reluctant to say that it was for IT online software and eventually told me it was for Microsoft. The guy is extremely rude, and I put him on hold then he hung up.

Company called Skillsets online (http://skillsetsitonline.com/)  trying to push online training for a bunch of stuff, can't take a hint that we're not interested. Called ID shows ups as Yajaira Rosario.

Called our main switchboard and asked for my extension, then cursed at the receptionist when she asked him what the call was in regards to.

I believe this is a spoofed number, same MO as described by IT MANAGER,
dumped into scammer voice mail and he didn't leave a message.  Why do they get mad when you thwart them?  Because they are scammers.

Scammer targeting IT companies.  Just block the number.