"have frequent contact" is a correct and usable phrase in written English.
You can use it when referring to ongoing communication or interactions between two or more people. For example, "My family and I have frequent contact with our neighbor."
The campaign has drawn interest among Chinese who have frequent contact with Americans.
Patients such as this are well known to services and have frequent contact, thus enabling proactive care.
The first voluntary registrations under the scheme of those who have frequent contact in paid or voluntary work with children in "regulated activities" – including teaching, care and supervision – were due to start on 26 July.
The result conveys that farmers who have frequent contact with agricultural experts are more likely to adopt new technologies.
This congruency suggests close relationships between the writer and recipient (Halliday and Matthiessen 2013), and that they were likely to have frequent contact and equal power relation (Eggins 2004).
Gatekeepers are people who have frequent contact with possibly suicidal members of the community on account of their professional status (e.g. railway personnel, security staff, fire-fighters, local charity workers).
A total of questionnaires were distributed to care team members (e.g. doctors, nurses, pharmacist, administrator, and technicians) who have frequent contacts with patients.
Although both of these locales have large Mexican-American communities that have frequent contacts with Mexican immigrants, he didn't answer a question that directly asked about the ethnicity of the U.S. cases.
Aggregation at a chosen place for a long period is a prerequisite of social organization, because close interaction between individuals is only possible if they have frequent contacts [6].
As in Africa, populations living in the Amazon River Basin have frequent contacts with water for domestic activities.
