Hi everyone

So we got a new car at the start of the year.... A DSA vehicle I believe it is a Peugeot gt line 3008 model. Well that's what my mum choose the vehicle is for my mum to drive my to and from uni. We used to have an Ford S max I believe it was..... Ok so the dog was able to get into the s max without a problem (he's a lab, he's mild hip dysplasia but is being treated) he was able to get in and out of the s max boot without a problem he always loved going in to the car but... Ever since we got the new car... The Peugeot 3008 it's almost as if he's afraid of going in a car again! As when I was at using throughout February-March-April and may we had to leave the dog at home as he just wouldn't get in the car... It's like he's afraid of it (I know the boot is higher in this car as well so I'm unsure if this is the problem or not but I've bought multiple different ramps and steps for the dog to try to get into the car but he just won't go I can't figure out what's wronge or what to do ?? I'm grateful that this semester was only one day but Septembers semester is supposed to be 4 days long and I can't leave the dog home all day without exercise as I'd be in from 9-5pm... Any advice on what to do or how to get the dog in? He doesn't even get excited when I say the word car anymore.... Please help I don't want the dog to be afraid of this care but he's not normally afraid of things... I dunno why he's acting thing way.. Any advice is appreciated!! As I'm currently trying to train to get in for next semester. I'm using the clicker with treats which he loves but it doesn't seem to work... And he's usually very responsive with clicker training :/ so this is why I can't figure out what's wronge. Please help