It is not possible to tell if there is a mistake in your understanding, because there are mistakes in your explanation.
What do you mean by “I have keyed in the market value of the currency…?” You do not enter market values of currency in Manager. Are you by chance referring to exchange rates?
Explain the circumstances for how, when, and where you found the value of a bank balance in the base currency on the basis of 31st March 2020. Without such information, your statement does not show a problem.
What are you referring to as a “currency table?” Manager has no such thing.
No, because Settings > Exchange Rates don’t trigger a Balance Sheet revaluation.
Exchange rates relate to transactions, that is, all transactions on or after Mar 31 will be at that rate, and all transactions on or after Jun 26 will be at that rate.
Let say you had Customers or Suppliers based in foreign currencies, their balances don’t change (get revalued) because of a fluctuation in currency exchange rates.
The balance sheet value of an asset or liability will restated in your base currency using the exchange rate that is current on the balance sheet date.
Obviously the balance in a foreign currency account will not change when reported in the foreign currency but it’s value on the B/S can change - the difference is posted to the Foreign Exchange gains/losses account
If you think something is wrong, then post screen images of the balances and the exchange rates to explain what you think is incorrect.
Post full screen images - the images you show above could be anything. You need to show the full screen as otherwise it is not possible to understand what you are showing
Maybe I didn’t understand you, but anytime the exchange rate is entered, there is a revaluation of all monetary asset and liabilities held in that foreign currency to the reporting currency/functional currency.
Debit/Credit: Monitory Items
Debit/Credit: FX gains and loses (Unrealised FX Gains and Losses)