[ic] continuing runtime error -- Can't locate object method "single" via package "Vend::Table::GDBM"

[Davideth]

 From the Admin interface, I am able to input and generate orders but 
when an order is attempted from the user interface, we get the same 
error over and over. I can not find any reference to method single 
anywhere. The shipping and shipmode pages are identical to those on 
another site which does not have this problem.


164.213.14.124 rF25JMhP:164.213.14.124 - [09/August/2018:12:30:43 -0500] 
paradevi /~paradevi/cgi-bin/cart.cgi/ord/shipmode Runtime error: Can't 
locate object method "single" via package "Vend::Table::GDBM" at 
/usr/local/interchange/lib/Vend/Ship.pm line 466.
 >
164.213.14.124 rF25JMhP:164.213.14.124 - [09/August/2018:12:30:51 -0500] 
paradevi /~paradevi/cgi-bin/cart.cgi/ord/shipmode Runtime error: Can't 
locate object method "single" via package "Vend::Table::GDBM" at 
/usr/local/interchange/lib/Vend/Ship.pm line 466.
 >
164.213.14.124 rF25JMhP:164.213.14.124 - [09/August/2018:12:30:54 -0500] 
paradevi /~paradevi/cgi-bin/cart.cgi/ord/shipmode Runtime error: Can't 
locate object method "single" via package "Vend::Table::GDBM" at 
/usr/local/interchange/lib/Vend/Ship.pm line 466.


The error page shows:

   _____________________________

Internal Server Error - Failed Script


    Server information

Internal Server Error - 500
"REFERRER " https://paradevices.com/~paradevi/cgi-bin/cart.cgi/ord/shipping
"Remote Addr "164.213.14.124
"Request URI "/~paradevi/cgi-bin/cart.cgi/ord/shipmode
"HTTP host " paradevices.com
"http User Agent " Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:61.0) 
Gecko/20100101 Firefox/61.0
"Redirect Status " 500