Help i have a black tie event to attend

[Badumdumdum]

And i have never been to one before and I always always dress wrong on formal occasions.
I have this lindy bop dress that i wore with heels and a waisted belt to a masquerade ball earlier this year. Would ut work?
www.lindybop.co.uk/emily-black-swan-border.html?pdg=kwd-302886143995:cmp-749411648:adg-44824551488:crv-176776665326:pid-5056061981517:dev-m&gclid=EAIaIQobChMI_dOgrZ7M2wIVxbDtCh15AQToEAQYBCABEgLFePD_BwE
Or too informal? To me its super posh with a big petticoat underneath it but I'm worried evert other woman will be in something slinky.
Its a work business event, my team is up for an award. I am a fairly new part time administrator and am not from a corporate/business background.
Iam 38 but could pass for 25, so can i get away with a younger looking dress? Like i think the lindy bop one is.

Heellpppp.

I agree with a Pp who suggested charity shops- could be a good call if you have the time.

And for everyone that said the lindybop was fancy dress- is there a need to be snide?

I don’t think it’s snide!

Lindybop is to my taste, which is entirely subjective, look like dress up dresses and seem to be the go to dress for women of a fuller figure. It’s not a look I like and I think makes the wearer look like the party entertainer rather than guest.
Festival wear, yes! Halloween party, yes! Hen do, go on! But formal event.... never. For me. In my little world where I expect my clothing attire would be viewed as dull.

I would wear the black one and dress it up with some smart accessories, it won’t look out of place