Potato vines can grow tall and very quickly. I've had to look after one in a garden and it never flowers as its always having to be pruned back.
I would move it to somewhere where it wont grow over the window. Keep it regularly pruned to keep it in check.
I would guess they reach 8 foot, but i know they get big

Is this Solanum laxum 'Album' - white flowers? If so, it is a vigorous grower - IF it survives the winter. They're not very hardy, and need a warm sheltered spot. I prune mine back by about a half to two-thirds every spring. If it takes off, it grows over the 6' trellis and into the field behind us - so that would be about 12', I suppose. A 4' wall isn't nearly big enough for it, and yes, the roots do tend to spread out.

Thank you for your answers. This is a small purple flower with a yellow centre. Would this one grow as tall, and can anything be planted near it.

Ah! That's S. crispum 'Glasnevin'. It's hardier than the white one, although it still needs a sheltered spot. It isn't a vine, it needs support, i.e. tying in to wires against a wall or trellis. It isn't nearly as vigorous as its 'brother', either, and you can prune it to keep it in its allotted space - but 4' is far too low. It would still grow above your wall. Mine is about 10 ' tall, trained against the back of a building facing west. I do prune it back to new shoots, but not hard-pruning like the S. laxum. Under it I have planted low-growing Euphorbias, and the roots don't bother them at all.

It sounds as if you need to find a more suitable position for it, if you can, or add a trellis to the wall, possibly?

Thank you once again.

Thank you once again.

You're welcome. :-)