Coordination Compounds: JEE Main 2025 Chemistry question

A metal complex with a formula $\mathrm{MCl_4.3NH_3}$ is involved in $sp^3d^2$ hybridisation. It upon reaction with excess of $\mathrm{AgNO_3}$ solution gives '$x$' moles of AgCl. Consider '$x$' is equal to the number of lone pairs of electron present in central atom of $\mathrm{BrF_5}$. Then the number of geometrical isomers exhibited by the complex is ______.