"Inadequacy" is the subject of your sentence, but there's no verb.  Everything you've written describes what kind of inadequacy you're talking about, but you don't say what it does or what it is.

An example of an action verb would be, "The inadequacy causes people to be angry."  "The inadequacy makes the tax payers lax in reporting."

An example of a being verb would be, "The inadequacy is outrageous!"  "The inadequacy is understandable given the circumstances."

Also, you two verbal modifiers of "inadequacy" should be of the same type   -   either both infinitives or both gerunds (objects of the preposition "in.")

The inadequacy to provide and to monitor  OR  The inadequacy in providing and monitoring

The inadequacy etc. in providing etc. and in monitoring etc. is causing the government to lose substantial revenue.   Predicate  (verb: is causing   -   present progressive tense)