Having a hard time directing dementia patients

I’m a fairly new cna ( care aide in Canada) I have worked in the hospital and another full care home as a casual in both places.
I am now part time in a full care home which is more like a dementia ward.

I’m soft spoken so I don’t believe I’m frightening the residents and patient. Maybe I’m too soft spoken.

I find it hard at times to deal with the dementia patients, if they don’t want to change for bed or doing their care. I was orientates by the head cna at this new facility ( I’m just two weeks in) and it took three of us to get this one resident into her pyjamas. At first it was myself and another recent graduate.
We tried everything and finally went to the head and told her the resident is refusing.
She said you have to do and came with us. The poor resident was afraid and as a result the head cna was punched in the breast.
I’ve seen her dealing with other residents and I know you need to be firm but we were also taught ( and I know school is different from real life) not to force them.
The head cna seems to have new bruises everyday but I don’t notice any other care aides with bruises.

Is she being too forceful? Any tips on the best way to deal with dementia patients? I know what we’re supposed to do but it doesn’t always work.

I get so nervous going into this place… I’m hoping it gets better.
Thanks 🙏