Hisense Smart tv

I bought a tv in July 2019 in a month time it showed a internal crack I took back to game store they told me they cannot help me,than they decided to take it to the repair,waited for response no response until I got an sms telling me I should come an take it,I went there without any explanation they gave back the tv if no explanation and the tv it’s still like that,mind it’s still on Guarantee it’s still new