Breast pump coverage question

I have been told by my insurance "all breast pumps are 100% covered" but then when I go to the approved supplier there is an upcharge for the pump I'm choosing. Has anyone else delt with this? Currently I'm waiting to receive a master list of all in network suppliers and going to have to contact all because they all seem to be charging different prices. Is there a better way?

I figured if they are 100% covered I should go with my first choice the Elvie pump but if not fully covered I'll likely choose a different pump. If you got one covered where did you order from?

Thanks in advance!