I have this sentence
"On the other hand, you can go to this page instead."
but I am not sure if the presence of both
On the other hand and
instead makes the sentence redundant.
... a tautology is a statement which repeats the same idea, using near-synonymous morphemes, words, or phrases, that is, "saying the same thing twice".
As to whether there is always error in it's use:
... it is often considered a fault of style when unintentional. On the other hand, an intentional repetition may be an effective way to emphasize a thought, or help the listener or reader understand a point.
All it's doing is unnecessarily restating information, it's not causing a logical conflict in the grammar, so its impact on meaning is harmless. More of a style issue than a grammar one.