Multithemes background images not responsive?

Hi
am using/trying out quite a few of these themes…but have noticed that any background images I use do not resize or behave responsively when viewed on tablets or phones…can anyone help or @multithemes

HI @pigglypots, which theme have this issue? can you send an email to infoATmultithemesDOTcom? thanks

Hi I have sent you an email directly…thanks for any help.