Dying clothes to cover washing runs

[PuffinNose]

Hi. I have a navy blue and white dress. The blue apparently is not colour fast. . The first time I washed it (according to the instructions) it turned the white a horrible manky grey/blue. The second time I washed it, this time with a colour catcher it turned the colour catcher really, really dark. I bought it BNWT from ebay so can't contact the company.
I really like the polka dot pattern and the original colour. If I get some of that colour restorer stuff will it affect the blue? If I use it, is it like bleach in that I won't be able to dye the dress afterwards?
If I dye it, what colour would you suggest? I was thinking maybe a paler blue but can't imagine it. I'm not very good with colour.
Thanks.

Was it a high street store? You can still take it back - it is defective. I had a Monsoon shirt, washed as per instructions and it shrank. Receipt was long gone but they exchanged it.

OutandIn did you even read the post? It clearly says bought from eBay

Yes i did read and my response is tge same - bnwt - if it is high street you don't need a receipt for an exchange as it is flawed.

Thanks OutandIntoday. I've already contacted Boden and they wanted the details of the person who bought it originally.