I searched at BNA for “Heard Hoopers”
Newspaper references to Mr Heard, Hooper(s)-square, [from 1817 Lemon-street is usually included in the address], Goodman's-fields start in October 1800. They are usually references to him acting as attorney in bankruptcies. These peter out at the end of 1823. In October 1824 he is named as one of the agents for the sale of a sale of property. Nothing after that with this search term.
Searched for "Heard Prescott"
two hits 1831, 1832 acting in bankruptcy cases
Searched for "attorney Mr Heard"
one hit, 1831
Searched for "Heard Great Prescott" several hits in 1828
searched for Mr Heard in the 1824-1828 gap
found a property sale Mr Heard, solicitor, 59, Prescot-street, Goodman's-fields in 1825
Did he move or was it simply that streets were renamed?
In any case he can’t have been born in 1788.