My first thought is possibly you accidentally poured washing-up liquid in the rinse aid container by mistake 🙁 The blue ‘Fairy Liquid’ is easily mistaken for ‘Finish Rinse Aid’ 😯
Otherwise simply ensure the lid seal on the rinse aid container is in good condition and that its regulator set around the mid way position 😉
Have you been using 3 in 1 tablets ❓
had same sort of fault custmor still had rinse aid in container and started using 3 in 1 tablets and it started to foam up. better to use seperate powder and rinse aid 8)