Den uautoriserede betaling undersøges, forudsat at banken får kortoplysningerne.

Because betaling is a common-gender noun in Danish: en betaling.

When a common-gender noun is definite and has an adjective before it, Danish uses den:

• en betaling
• den uautoriserede betaling

If the noun were neuter, you would use det:

• et kort
• det nye kort

In Danish, adjectives usually take -e in a definite noun phrase after den, det, or de.

Compare:

• en uautoriseret betaling = indefinite
• den uautoriserede betaling = definite

So the -e ending here is not random; it shows that the noun phrase is definite.

Because Danish normally does not use the noun’s definite ending when there is already a separate definite article plus an adjective.

So:

• betalingen = the payment
• den uautoriserede betaling = the unauthorized payment

This is a very common Danish pattern:

• bilen = the car
• den store bil = the big car

So once you have den + adjective, the noun usually stays in its basic form.

Undersøges is the present passive form of undersøge.

• undersøger = investigates / is investigating
• undersøges = is investigated / is being investigated

Danish often forms the passive with -s, especially in formal or official language. That is why this sentence sounds a bit administrative.

Yes. Den uautoriserede betaling bliver undersøgt is also correct.

Both are passive, but they can feel slightly different in style:

• undersøges = often more formal, compact, bureaucratic
• bliver undersøgt = also very common, sometimes a bit more neutral or everyday

In this sentence, undersøges fits the formal banking/legal tone well.

Forudsat at introduces a condition. It means something like:

• provided that
• assuming that
• on condition that

It is more formal than hvis.

So:

• hvis banken får kortoplysningerne = if the bank gets the card details
• forudsat at banken får kortoplysningerne = provided that the bank gets the card details

The second version sounds more official and precise.

Because at introduces a subordinate clause.

In Danish:

• main clauses usually follow the verb-second pattern
• subordinate clauses usually have subject + verb order

So:

• main clause: Den uautoriserede betaling undersøges
• subordinate clause: at banken får kortoplysningerne

That is why banken comes before får here.

It is a Danish compound noun, and Danish writes compounds as one word.

It is built like this:

• kort = card
• oplysninger = details / information
• -ne = definite plural ending

So kortoplysningerne means the card details or the card information.

A useful thing to remember: in Danish compounds, the last part carries the grammar endings. That is why the plural/definite ending appears at the end of the whole word.

Because Danish often uses the present tense for conditions and future-related situations when the context is clear.

So forudsat at banken får kortoplysningerne can refer to a future condition, even though får is present tense.

English often works similarly in conditional clauses:

• if the bank gets the details not usually
• if the bank will get the details

So the present tense here is completely normal.

The comma separates the main clause from the subordinate clause.

In Danish, comma usage before subordinate clauses depends somewhat on which accepted comma system is being followed:

• one system uses a comma before the subordinate clause
• another often leaves it out

So this comma is natural and standard in one common system, and you may also see similar sentences without it. The important grammar point is that forudsat at banken får kortoplysningerne is a subordinate clause.