error call to a member function getcollectionparentid() on null

Learn how to troubleshoot and fix the “Error Call to a member function getcollectionparentid() on null” in Magento. This comprehensive guide covers step-by-step solutions to resolve this common issue after platform upgrades. Troubleshoot and fix the “Error Call to a member function getcollectionparentid() on null” in Magento with this comprehensive guide. Learn step-by-step solutions to…