Transfer goddady domain to namecheap hosting!!

I want to transfer a domain name from goddady (because it's cheap a little compared to namecheap domain)to namechape hosting , but it says(namecheap) it can't be possible because according to them the domain name that i've chosen is already exist in their marketplace

Follow the instructions here:
https://www.namecheap.com/support/k.../876/83/how-to-transfer-a-domain-from-godaddy
https://uk.godaddy.com/help/transfer-domain-to-another-registrar-3560

If you run into problems you will need to contact both GoDaddy and NameCheap support for help

You can try changing DNS Nameservers of Domain Name to your namecheap hosting & then host it.
It will be live on NameCheap Hosting.