In practice, very little can be done.
There are a couple of scenarios that could be described.
Firstly it may be that the government or the body running the election is basically fair. However either it is interpreting its own rules too exactly, or its rules are unclear and being applied inconsistently, or there are various local problems. In most cases, this would mean that either the problems would not have changed the result of the election. Or that the result stands even though some might see it as unfair. In this situation, it is unlikely that there will be any way for a person to vote, or get a re-run of the election.
If the election is so disrupted as to make the result completely invalid, then the goverment might choose abandon the election. An example of this might be a major earthquake that means that it is impossible to run the election. Such an act may be extraconstitutional.
For example if the rules state, "you must be inside the polling station before 11pm CET" and don't allow for any flexibility for people queuing outside. And the rules were published and agreed in advance, then merely applying the rules doesn't mean the vote is invalid, even though it may seem unfair.
The other scenario is that the government is basically unfair, and are holding a deliberately rigged election. In which case, there is no reason to think that the government would want to re-do the election. The only way to get a vote would be from outside action, for example through the European Court. Such a process is extremely slow.
In general, anyone can sue over anything, but in order to sue successfully, you would need to demonstrate the damage that is done to you as an individual, and it is very hard to demonstrate the damage done to an individual in such a way that a court can award damages. You would also need to show that the rules were being broken.
If the result is in doubt, then there may be action that can be taken through the constitutional courts by the losing campaign. But this can't be done directly by an individual voter.