CRITICAL ERROR - Call to a member function getName() on null

A couple of things you can check while you wait for the Devs to see your post:
1) Do you have any overrides created in /Templates/*YOUR*TEMPLATE*/html/com_eventbooking/? Rename this com_eventsbooking folder and test to see if that fixes the problem. If it does, then you'll have to narrow down which override.
2) On my site, payment options looks like it loads after Final Cost. Check each of your payment plugins to make sure that the proper info in entered in each one. Maybe an update accidentally cleared some info or new info is required. Make sure you have a payment plugin(s) specified too. I can see at a code level that there are several calls to getName in various payment-related files. Do you use a custom payment plugin? Maybe that needs updating?

@Tuan will undoubtedly have better insight into specific reasons that this error could show up...

Thanks a lot, my customer disabled all payments plugins...so mark this topic as SOLVED

Thanks!

Great. Thanks Luca for confirming that it's solved and thanks James for help answering the questions

Tuan

Thanks guys. Had the same error and it was due to having no plug published.