When using the verb "help," you can use either a to-infinitive or a bare infinitive without affecting the meaning or the grammaticality of the sentence. The bare infinitive version is more common especially in American English.
"[...]the better practice is to use a bare infinitive after help (if the choice is between a fully expressed infinitive [with to] and a bare one [without to]) [...]
"The bare infinitive form after help overtook the to-form in the late 1960s and remains more than twice as common with various verbs."
Garner (2016), Garner's Modern English Usage. Oxford University Press.