When DD got scared of the bath we first tried doing something fun... Maybe put her in the bath in a tshirt or something (that you can take off later) so she doesn't realise she is getting a bath

Anyway, my DD is obsessed with dolls and babies, so we gave her baby doll a bath... she loved doing this, and then i could give her a bath once she was in there and having fun.

Maybe if you got in with her? that also might calm her down?