Hello,
The dropdown style of Variants might be appearing on your Site for the Products due to the Attributes that you might have used under a Product are not the ones defined under the Dashboard > Products > Attributes. You might have added the Attributes something like this on your Site:
https://snipboard.io/KUQvFd.jpg
So, if you have done something like that then you have chosen a bit of an incorrect way. You need to use the Attributes on your Products that are defined under the Dashboard > Products > Attributes > and then add them under the Products like selection style not the vertical line style, please refer to the image for reference: https://snipboard.io/j7dy5M.jpg
Because if you use the Attributes for the Products which are defined on your Site under the said location then you just need to select the values for the Attribute values, you don’t need to define them all manually like you have currently right now.
If this isn’t the case on your Site, then kindly please share your Site WP-ADMIN Login details in the Private Content field so that we can check this concern on your Site and help you out accordingly.
Best Regards