CAn you tell me if it is possible to set up automatic payment dates with this company?

I have a parent who is late every month and tbh I'm sick of it. It's very few hours so I know she thinks it doesn't really matter and always has an excuse. This month she told me they were way until the 30th I said that's ok as long as the tau ate the vouchers that very same day. Well I've still heard nothing. Have emailed a polite reminder saying they must pay ASAP to avoid a late charge but still nothing. And so I'm cross.

I'd like to suggest they set up automatic payment but not sure if it's possible to do that when the invoice is different each month.