This is a common problem for new users, getting into SPUFI for the first time. The default isolation level for SPUFI is RR (repeatable read), which we've observed on many occasions to cause problems as users will get into SPUFI, run a query (in RR isolation level), and leave their SPUFI session open, thus leaving locks on the table being queried.
In response to this, we have "locked down" the default DSNESPRR plan for SPUFI in order to prevent people from using it. The more appropriate plan to use would be the DSNESPCS plan, which sets the isolation level to CS (cursor stability).
If you have received the above error, the appropriate way to set you SPUFI plan to the "approved" DSNESPCS plan is as follows:
On the main SPUFI menu, select option 5 "Change Defaults". This will bring you to the "Current SPUFI Defaults" panel. Change option 2 "Isolation Level" from "RR" to "CS" and hit enter. This should take care of the problem you've experienced.