You have to first issue a notice to the people who are occupying the shop to vacate the same questioning their legal validity or base as they are not legal heirs to the deceased tenant.
The legal heirs of the deceased tenant can occupy the rented property for a maximum period of five years after the death of the deceased tenant.
But these people are not legal heirs at all,
They cannot get a legal heirship certificate from the revenue department being class II or III legal heirs.
They have to get a succession certificate from a court of law only. You can file an injunction suit against them restraining them from occupying the shop and to declare the same as illegal. Dont file an eviction suit, you can seek ejectment due to their illegal possession.