I need to set up GA4 on an eCommerce website

We had universal analytics set up on a eCommerce website and tracking conversions but since moving to GA4 we have seen that the tracking isn't working correctly and we are missing conversions/purchases. We need to sort this issue as soon as possible so we need some assistance from a GA expert (we are very competent but there are always levels to the game).

Please do get in touch if you feel you can help - we may need assistance on other websites as well ;-)