I understand that this has been asked many times before. But I haven't been able to find a conclusive answer or guide to solve the issue.
When we add a new product to an opportunity we get the following error.
Apex trigger npsp.TDTM_Opportunity caused an unexpected exception, contact your administrator: npsp.TDTM_Opportunity: System.LimitException: Query of LOB fields caused heap usage to exceed limit.
This has only just recently started occurring after 12-months of usage - and the person who originally developed this for us is not longer available.
As a not-for-profit, we can't exactly go out and find another developer to amend this for us, so any help would be greatly appreciated.