To resolve this, slowly pump up the tyre, ensuring the bead of the tyre is seated on the rim. Pump a bit of air in the inner tube which helps to keep the tyre seated! Then slowly pump up the tyre checking the that the tyre remains fitted all around the rim.
Secondly, if you are fitting the same tyre from your original wheel you may find that the tyre has stretched over time, this is perfectly normal with wear, you will likely need a new tyre which is true to the size of the Swytch rim.