21 month old won’t give up the bottle

I know everyone says that you should take away the bottle around 1 year. My daughter nursed until 15 months and has been taking a bottle ever since. But she will not nap, sleep, or go back to sleep without one! I’m not sure if I should continue trying to take the bottle away, or just let her be a baby. Is it really THAT bad? We brush her teeth before bed and when she wakes up in the morning and she usually doesnt just sleep with the bottle in her mouth. TIA!