undersubscribe

verb (T) be undersubscribed if an activity, sale, service etc is undersubscribed, not many people want it undertake, verb past tense undertook /-'tUk/ past participle undertaken (T) formal

1 to accept that you are responsible for a piece of work, and start to do it: She undertook full responsibility for the new changes.

2 undertake to do sth to promise or agree to do something: He undertook to pay the money back in six months.