Hi,
This means that there is an error in the file plugins/hikashoppayment/hsbc/hsbc.php
However, I don't see that error on my end.
So the file must have been modified on your end for some reason I don't know.
Download the HikaShop install package on our website, extract it on your computer and copy the files from the folder back/extensions/plg_hikashoppayment_hsbc/ from the the install package to the folder plugins/hikashoppayment/hsbc/ of your website via FTP.
That should hopefully fix the problem.