Acabamos de completar el formulario de cargos no reconocidos.

The pattern acabar de + infinitive means to have just done something.

So:

• acabamos de completar = we have just completed
• literally, we finish from completing does not work in English, so you should learn it as a fixed structure.

More examples:

• Acabo de llegar = I’ve just arrived
• Acaban de llamar = They’ve just called

In this sentence, it tells you the action was completed very recently.

Because in Spanish, acabar de + infinitive uses the present tense of acabar to express recent past.

So even though acabamos looks like we finish, the full structure means we have just...

Compare:

• Completamos el formulario = We completed the form / We fill out the form depending on context
• Acabamos de completar el formulario = We have just completed the form

This is a very common Spanish way to talk about something that happened moments ago.

Because acabar needs de in this grammar pattern:

• acabar de + infinitive

You cannot say:

• acabamos completar ❌

You must say:

• acabamos de completar ✅

Here, de is simply part of the structure. It does not mean of in the usual sense here.

That de has a different job. Here it means something like for or about.

• el formulario de cargos no reconocidos = the form for unrecognized/unauthorized charges

So the sentence contains two different de words with two different functions:

• acabamos de completar → part of the grammar structure acabar de + infinitive
• formulario de cargos no reconocidos → links the noun formulario to what the form is about

This is very common in Spanish.

Spanish often leaves out subject pronouns because the verb ending already shows who the subject is.

• acabamos clearly means we

So:

• Acabamos de completar... = We have just completed...

You could say:

• Nosotros acabamos de completar...

but it is usually unnecessary unless you want emphasis, contrast, or clarity.

In this context, cargos means charges, usually financial charges, such as:

• credit card charges
• bank account charges
• transactions on a statement

It does not mean jobs, positions, or responsibilities here, even though cargo can have those meanings in other contexts.

So cargos no reconocidos refers to charges the account holder does not recognize.

Because no reconocido is the more natural choice for financial charges or transactions that the person says they did not make or do not identify.

• cargo no reconocido = an unrecognized charge
• cargo desconocido could be understood, but it sounds less standard in this banking context

The nuance is:

• no reconocido = not recognized by the customer
• desconocido = unknown, more general

Banks and payment providers often use wording like cargos no reconocidos for disputed transactions.

Because reconocidos describes cargos, and adjectives/participles in Spanish usually agree with the noun in gender and number.

• cargo = masculine singular
• cargos = masculine plural

So:

• cargo no reconocido
• cargos no reconocidos

The no does not change, but reconocido changes to match cargos.

Because no reconocido works as a standard negative adjective phrase meaning not recognized.

So:

• cargos no reconocidos = charges not recognized

This is normal Spanish word order. The no directly modifies reconocidos.

You should think of no reconocido as a common unit, especially in formal or administrative language.

Using el suggests a specific form, probably one already known from the situation.

• el formulario = the form
• un formulario = a form

If you are talking about the official form for reporting those charges, el formulario is very natural.

In real contexts, Spanish often uses the definite article where English also uses the.

Yes, but the meaning changes slightly.

• Acabamos de completar el formulario = We have just completed the form
• Hemos completado el formulario = We have completed the form

The second version states that the action is done, but it does not emphasize that it happened just now.

So if the idea of very recently matters, acabamos de completar is better.

It is correct and natural, especially in formal or administrative language.

However, in Spain you will also often hear:

• rellenar un formulario = to fill in a form

So these are both possible:

• Acabamos de completar el formulario...
• Acabamos de rellenar el formulario...

Very roughly:

• completar can sound a bit more formal or neutral
• rellenar is extremely common for forms in Spain

Both are good Spanish.

It sounds fairly neutral-to-formal because of the vocabulary:

• completar
• formulario
• cargos no reconocidos

This sounds like customer service, banking, or administrative Spanish. It is not overly stiff, but it is definitely not very casual speech.

In everyday conversation, someone might say something a little simpler, depending on context, but this sentence is completely natural for official or practical situations.