iPhone 11 using an external wireless mic with live sound to bluetooth speaker

I bought a wireless microphone for iphone so that I can send live sound to a bluetooth speaker and use a PA. I have used the iOS app called 'microphone' and can use the phone's internal speaker while playing music to my bluetooth speaker and it works perfectly but I need a hidden lavalier rather than hold an iPhone while I am performing. When I plug the mic's transmitter to the phone it disables sound output, I think the phone thinks the mic is a speaker or headphones. I can use the mic to record on the phone, so the mic is working but cannot live monitor or have any sound output from the phone while the external mic is plugged in. Is there a work around?