is it a normal shop lot gym or branch gyms like fitness first?

Is it normal shoplot gym - then you probably cant do much or may be just go talk to management or boss ask to open earlier. If fitness first level gym - then call hq and complain.

I doubt the gym Start with F. Most gyms having a tough time operating now probably why they employ unreliable staff and expect this type of work ethic. I think it's time for you to look for other gyms.