Hi Lydia. Thank you for reaching out to us. This is Joanne T from Airbnb's community support team and I hope that this message finds you well.
I would like to let you know that I just received your ticket. I will make sure to work with you on this ticket until we solve this.
I understand that you would like to know why there is an error when you tried to accept a booking request.
As a Co-host , you can Accept, decline, cancel, or change reservations. Co-Hosts can’t accept/decline/alter/cancel reservations on mobile. I recommend you to accept the reservation using your computer.
You may visit this help center article for more information.
www.airbnb.co.in/help/article/1534
Please don't hesitate to let me know if there's anything else I can help you with.
Regards,
Jo-Anne