Is working in the field of international calls via the internet, which some countries may prohibit to monopolize profits for their telecommunications companies, considered permissible or forbidden, taking into account that this work provides calls at a low price for citizens?

If the use of such means does not involve harm or infringement on the rights of telecommunications companies, and the prohibition is merely for profit maximization and monopolization of communication means, then compliance with the prohibition is not obligatory, and there is no sin in violating it; due to the absence of a general legitimate interest. However, if their use involves infringement on the rights of companies and causes them harm, then it is not permissible. It is obligatory to adhere to laws that protect property rights and the public interest.