Botox duration— moving goalpost?

Hello! Is there a credible max timeline for btx to wear off under eyes? I had terrible effect from 3 units by a cred dermatologist (huge wrinkle when I smile where cheek meets tear trough). Was told 3/4 months but it did not resolve. I’m now 6 months out and there is more movement and tiny lines but the huge wrinkle is still fully there. The goal post keeps moving and I am trying to hold out hope but what is the realistic max wait? I just want to feel normal again. Thanks so much!!