Apologies I need another bra intervention

[Veins]

Okay measurements are as follows

35 under boobs
39 over boobs

What should I be wearing?

Try a 34D as a starting point, you may well need a DD

I bought some 34DD's but they leave red marks on my back and I have the dreaded 'back fat'. So I'm getting something wrong.

Red marks are ok, I get them (it's like jeans or a waist band) How did the back and cup feel

It just felt like it was cutting into me

OK, few questions:

What bra is it?

Can you try it on back to front - this isolates the cups so you can see how the band fits in isolation

Then, can you put it on properly and try scooping - the back fat needs to be scooped in to the cups.

It's a Debenhams bra. Gorgeous range? Band fits fine in isolation but the minute I turn it round have back fat and scooping doesn't seem to put it all in. It's like muffin top in jeans at the back. I am a size 14 and not toned.

Ah, ok

First up - Debenhams gorgeous are notoriously small :)

Now, when you say it doesn't pull in when you scoop - are the cups already full? If so, you need a bigger cup rather than band - if there isn't enough space in the cup then scooping doesn't work as it all just slides back out!

Yes, when I scoop my boobs fall out of the cups. Does that mean I'm an E cup?

OK, that's the problem. If you fall out after scooping, you need more cup space. The measurement is only ever a starting point. Try an E, and possible even an F. Scoop like crazy before you decide if it fits - many of my bras look a bit empty until I've scooped.

This is probably what's causing the back fat to be so bad - the cups don't have enough room.