Contactei a linha de avarias.

Contactei is the 1st person singular form of contactar in the pretérito perfeito simples.

That means it refers to a completed action in the past: I contacted.

So:

• contacto = I contact / I am contacting (depending on context, but usually present)
• contactei = I contacted
• contactava = I used to contact / I was contacting

In this sentence, contactei tells you the action happened and was completed.

Portuguese often omits the subject pronoun when it is clear from the verb ending.

In contactei, the ending -ei already shows that the subject is I.

So both are possible:

• Eu contactei a linha de avarias.
• Contactei a linha de avarias.

The second version is very natural and common. Portuguese does this much more often than English.

Here, a is not a preposition. It is the feminine singular definite article: the.

• linha is a feminine noun
• so the line = a linha

In Contactei a linha de avarias, the verb contactar takes a direct object, so there is no preposition before a linha.

So this sentence is literally structured like:

• I contacted the fault line

not

• I contacted to the fault line

Because contactar is a direct transitive verb. It normally takes its object without a preposition.

So you say:

• Contactei a linha de avarias.

not:

• Contactei para a linha de avarias.

However, if you use ligar for making a phone call, then you usually use para:

• Liguei para a linha de avarias. = I called the fault helpline.

So:

• contactar alguém / alguma coisa
• ligar para alguém / para algum número

Linha de avarias is a common service expression in Portugal. It usually means a fault-reporting helpline or breakdown line, especially for services such as:

• electricity
• water
• gas
• internet
• telephone service

Here, linha means something like phone line, helpline, or service number, not a physical line drawn on paper.

And avarias means faults, malfunctions, or breakdowns.

So the whole expression refers to the service you contact when something is not working.

In this kind of service label, Portuguese often uses the plural because it refers to the department or line that deals with faults in general, not just one specific fault.

So:

• linha de avarias = fault-reporting line / breakdown helpline

If you were talking about one specific issue, you might say:

• Tenho uma avaria. = I have a fault / breakdown.
• Há uma avaria na rede. = There is a fault in the network.

The plural in linha de avarias is just part of the normal fixed expression.

Both are possible, but they are slightly different in nuance.

• Contactei a linha de avarias = I contacted the fault helpline

  • more general
  • does not focus only on the phone call itself
  • could sound a bit more formal or neutral

• Liguei para a linha de avarias = I called the fault helpline

  • specifically about making a phone call
  • often very natural in everyday speech

So if you want to emphasize the phone action, liguei para is often the most idiomatic choice. If you want a broader or slightly more formal statement, contactei works well.

In European Portuguese, the usual spelling is contactar, with c.

That is because in Portugal the c is pronounced. The same happens in:

• contacto
• contactar

This is one of the differences learners may notice between European and Brazilian Portuguese. In Brazil, forms without that c are common, such as contatar.

So for Portuguese from Portugal, contactei from contactar is the expected form.

The normal word order is:

• Contactei
  • a linha de avarias

That is the standard verb + object order.

You could also say:

• Eu contactei a linha de avarias.

And in some contexts, you might move things around for emphasis, but the basic version is the most natural.

For a learner, the safest pattern is:

• [verb] + [direct object]

So this sentence is a good model:

• Contactei a linha de avarias.