Use caution
Electrolux groups i20 with C2, F2, AL6, two beeps, or two LED flashes and says the signals indicate a drainage problem.
Source scopeElectrolux UK freestanding and integrated dishwasher support
Applicability boundaryThe aliases and signals are grouped by the cited article; confirm them in the exact model or PNC manual.
Safe next stepClean the user-removable filters, inspect the visible drain hose and recent sink connection work, then arrange service if drainage does not resume.
Sources: [1]