Over Amount(more than Transferable Balance) Staking Issue.

[johnnyji-dev]

I want to confirm the internal staking logic.
I found some issue for staking by using polkadot.js.

[ENVIROMENTS]
TestCase01)
Network : SHIBUYA testnet
Before Test - Account State: Transferable(65.130xxxSBY) | Staking(15SBY) | Unstaking(5SBY)
Test Transaction : dAppStaking("Evm": "0x772d8eecb77545feb8d19f7649f6be942bfd1cf9", Amount 80SBY)
After Test - Staking Transaction Success / Account State: Transferable(1SBY) | Staking(74.130SBY) | Unstaking(5SBY)
https://shibuya.subscan.io/extrinsic/0x478908544239cc56626cf1cb1717b288e1e4d6b39aab1a11c791494d6317e386

TestCase02)
Network : ASTAR mainnet
Before Test - Account State: Transferable(603.194xxxASTR) | Staking(0ASTR) | Unstaking(502ASTR)
!!Test Transaction : dAppStaking("Evm": "0x48f292e9fdce07ba34217b0aa62e08b62376df3e", Amount 1104.220xxxASTR)
!!After Test - Staking Transaction Success / Account State: Transferable(1ASTR) | Staking(602.194xxxASTR) | Unstaking(502ASTR)
https://astar.subscan.io/extrinsic/0x8663d8fbccf989aec329df725c0e1e2ad2ac2fc99a780576004f7b49b56bd903

[Questions]
Both TestCases run Staking transaction with over amount.

1. How to decide a final amount of staking value, when the value is set to a value more than the amount of Transferable.
   I guess based on two TestCases that the network(Node) processes the value of oversetting to {Transferable-1}.
   Can I convince that upper-guess is true?