Multiclassing Wizard6/Eldritch Knight14. Pretty sure I'm supposed to have access to level 4 and 5 spell slots but the builder only gives me options up to level 3, am I missing something?

3rd level is correct.

The multiclassing rules state:

You determine what spells you know and can prepare for each class individually, as if you were a single-classed member of that class.

Eldritch knights at level 14 and wizards at level 6 both have access to 3rd level spells and no higher.

You count as a 10th level caster for determining the spell slots you have access to, but that doesn't change the above.

Thanks, was using a multiclass spell calculator, might have missed something since they both use the Wizard spell list