Nami.getAssets() providing empty array and Nami.send() is not working giving error expected instance of BigNum

[Mahad-Ahmad]

Nami.send({ address:
'addr1q9zuz87pdpavf4qv887ku2d5u3cvamz8v7mlzqdm6rw62jln442xmqc6emat80hua9a5sdf5jsavm22mkp7c2ka80c2suk45r7',
amount: 20,})
Unhandled Runtime Error
Error: expected instance of BigNum

Call Stack
_assertClass
node_modules/@emurgo/cardano-serialization-lib-browser/cardano_serialization_lib_bg.js (193:0)
Module.min_ada_required
node_modules/@emurgo/cardano-serialization-lib-browser/cardano_serialization_lib_bg.js (341:0)
Object.eval
node_modules/nami-wallet-api/lib/index.js (243:0)
step
node_modules/nami-wallet-api/lib/index.js (52:0)
Object.eval [as next]
node_modules/nami-wallet-api/lib/index.js (33:45)
fulfilled
node_modules/nami-wallet-api/lib/index.js (24:42)