I got a job in Dubai but they are saying that my...

If your inquiry is about obtaining a work contract in Dubai, but your old work visa has not been canceled since 2017, find the following information:
In order to cancel the old visa, it is necessary to contact the former sponsor in the UAE, so that he / she visit and review at the general administration of residence and cancel the old visa.
If a previous sponsor does not respond with your request, then you can use any of your friends who are residing in the UAE and to let him / her to file a complaint at the General Administration of Residence against the previous sponsor on your behalf.