Toddler scared of hair being washed

My 2 year old has recently become terrified of having her hair rinsed out in the bath tub. She had 1 incident where she moved her head as I was rinsing & it got in her face. Ever since then she’s been scared.

We got one of these today hoping it would help

But she freaked out.

She doesn’t mind getting her hair washed but the minute I have to wet it to wash or rinse the shampoo out she freaks.

She’ll scream, cry, stand up & get out of the tub & try to run out of the bathroom, she’ll knock the cups out of my hand, she’ll get to the furthest corner of the tub away from me...

what can I do to help??