Fingerprint won't work after screen replacement?

Hi,I ordered a new LCD and touchscreen on aliexpress and went to the local store to replace it,now the screen is working but the fingerprint won't work,it always say:"Make sure that the Home key is clean and dry, then try again" but the button is clean and dry.I tried to restart it but nothing. At the local shop they said that they could reinstall the system for some money,my question is, can I reinstall it by myself and how or does someone have the same issue and a working solution?Thanks...