23.1.&nbsp. &nbsp;</strong>This Agreement may be materially altered by IONOS by posting the new version of the Agreement at&nbsp;www.ionos.com and if posted in this manner, shall be effective immediately upon posting such notice. In the event that IONOS does materially change the terms of this Agreement, you accept and shall be bound by such changed terms unless you opt to terminate the Agreement within thirty days of the posting of notice of such change.</p> <p> <strong>23.2.&nbsp. &nbsp;</strong>You may not modify this Agreement, in whole or in part, and any such modification or attempt to modify shall not be enforceable unless reduced to writing and signed by a duly authorized representative of IONOS.