Hubo un malentendido con la reserva, y por eso nos dieron otra mesa.

Hubo is the preterite of haber used impersonally, and here it presents the misunderstanding as a completed event: there was a misunderstanding.

• Hubo un malentendido = there was a misunderstanding
• Había un malentendido would sound more like “there was / there used to be / there existed a misunderstanding” in a more descriptive background sense.

In this sentence, hubo fits because the misunderstanding is treated as a specific incident.

Here, hubo comes from haber, but not in the usual auxiliary sense like he comido.

It is the impersonal form meaning there was / there were.

Examples:

• Hubo un problema. = There was a problem.
• Hubo muchas quejas. = There were many complaints.

Even if the noun is plural, this impersonal haber stays singular:

• Hubo problemas, not hubieron problemas in standard Spanish.

Malentendido means misunderstanding.

It comes from:

• mal- = badly / wrong
• entendido = understood

So literally it is something like wrong understanding.

Very common expressions:

• Hubo un malentendido. = There was a misunderstanding.
• Fue un malentendido. = It was a misunderstanding.

Con la reserva is the most natural way to say with the reservation / booking, meaning the misunderstanding was related to it.

So:

• Hubo un malentendido con la reserva = There was a misunderstanding with the booking/reservation.

You might also hear:

• sobre la reserva = about the reservation
• respecto a la reserva = regarding the reservation

But con is very natural in everyday Spanish when talking about a problem connected to something.

It can mean either in general, but in this sentence it most naturally means a restaurant booking, because the next part mentions otra mesa.

So here:

• la reserva = the booking / reservation for the table

In Spain, reserva is a normal word for this kind of booking.

Por eso means because of that / that’s why / for that reason.

In this sentence:

• Hubo un malentendido..., y por eso nos dieron otra mesa.
• “There was a misunderstanding..., and because of that they gave us another table.”

Compare:

• porque = because
• por eso = because of that / that’s why

Examples:

• Nos fuimos porque era tarde. = We left because it was late.
• Era tarde, por eso nos fuimos. = It was late, so / that’s why we left.

Nos means to us in this sentence.

• dieron = they gave
• nos dieron = they gave us

Spanish often uses an indirect object pronoun even when English may just say gave us.

Structure:

• dar algo a alguien = to give something to someone
• nos dieron otra mesa = they gave another table to us

You could also say:

• Nos dieron otra mesa a nosotros but a nosotros is usually only added for emphasis.

Spanish often leaves the subject unstated when it is understood from context.

Here, dieron is they gave, but Spanish does not need to say ellos.

So the implied subject is something like:

• the restaurant staff
• the host
• the people in charge

Adding ellos would usually sound unnecessary unless you want emphasis or contrast.

Dieron is the third person plural preterite of dar: they gave.

• dio = he/she gave
• dieron = they gave

Since the sentence refers to an unspecified group of people at the restaurant, dieron is the natural choice.

In Spanish, otro / otra normally does not take un/una before it.

So:

• otra mesa = another table

Not:

• una otra mesa

This is different from English, where another historically includes the idea of an + other.

More examples:

• otro día = another day
• otra opción = another option

Yes, but it is slightly different in feel.

• otra mesa = another table
• una mesa diferente = a different table

In many contexts they are close, but otra mesa is the more natural everyday choice here. It suggests they originally had one table planned and then gave you a different one instead.

Because the sentence tells a completed sequence of events in the past:

1. Hubo un malentendido
2. Nos dieron otra mesa

This is classic preterite territory in Spanish: specific events that happened and were completed.

If the sentence were giving background or describing an ongoing situation, the imperfect might appear instead, but here it is telling what happened.

Yes. Spanish word order is flexible, although the original version sounds very natural.

Possible variations:

• Por eso nos dieron otra mesa: hubo un malentendido con la reserva.
• Nos dieron otra mesa porque hubo un malentendido con la reserva.

All are grammatical, but the original:

• Hubo un malentendido con la reserva, y por eso nos dieron otra mesa. is a very natural way to tell the story in order.

Not especially. This sentence is standard Spanish and would be understood across the Spanish-speaking world.

A couple of notes:

• In Spain, reserva is very common for a restaurant booking.
• In some contexts elsewhere, people might also say reservación, especially in parts of Latin America.

But the whole sentence is neutral and widely natural.