Caller: Told to be Fairwork Ombudsman but got empty voicemail now im concerned its a scam

Got postal letter Supposedly from Fairwork Ombudsman Sydney office to call this number but got empty voicemail, and then received calls all afternoon from a foreign number from Tunisia +21626720677. Are they related?? Its a bit suspicious. The email in the letter was from patrizia.grella @ fwo.gov.au. Which asked for my contact and age which i was then told didn't match their records. I hope it wasnt a scam but will see if anything further happens. I wont give out any other info.

I called back number (02) 8293 4939 reached voice mail but did not say for what company.