If the receipt total/amount field is using the Payement Txn field - "Transaction Amount", then this will show the amount with the Currency field. For example as shown below
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To changed this, select use the Letter Form Builder [Beta] button on the Letter object and drag/drop another field - for example "Total Amount" to replace this field. You can change the column heading to still have the label "Amount" if that is required.
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The updated receipt will now NOT have the Currency, but will show the Currency symbol.
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