I cannot submit the settings of a plugin, Participants Database

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Hi, I cannot submit the settings of the plugin, Participants Database in the site. I am hosting this site in the Bluehost company. I have had no problem in submitting the settings of the plugin in a site that is being hosted in a University server. I have done enough to solve this issue through communicating with the Bluehost and the plugin author. And you know, their answer is, "There is no problem in their sides and ask the plugin author or the hosting company." I desperately need to use the plugin. You are my last hope to solve this issue. Could you please help me solve this issue? Could you at least point out the cause of this problem?
Thank you for your help.