I think that my parents were victims of contractor fraud?

they contacted this roofer in the spring to do the roof on a second house they own ( was originally owned by grandparents )

they paid a deposit ( a large % of actual cost of the job ) in May and were told materials would be purchased with the deposit and that job would start and be finished in May

well its now almost September and roof has yet to be even started and not 1 single piece of material has ever been delivered to that address

from what i know they found this roofer online and i checked his online views and there actually all really positive , only red flag to me was the most recent reviews were from 5 months ago , meaning he hasn't been active this year despite claiming to be and taking money / orders

they contacted him this week and get told same story every time , that he's going to get on it soon etc yet no evidence of that and no materials ever brought to that house yet despite paying a deposit for them

Updates
1 y
still no sign of this roofer , they've got new messages from him saying he's coming. he claims to be busy with other jobs but his google views have no reviews from anyone more recent than 6 months ago. other than 1 new review which appeared today , " They came and solved my issue promptly and professionally! Highly highly recommend!!!" which oddly claims he came quickly? so perhaps he's back in business? but its like October here and time running out to do a roof before winter
I think that my parents were victims of contractor fraud?
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