Your contract binds both of you: the contract is the law of the parties; it cannot be revoked or amended except by their agreement or for reasons fixed by law (art. 147). On breach, in bilateral contracts, if one party fails to perform, the other may — after putting the debtor on notice (i’dhar) — demand either performance or rescission, with compensation in either case where warranted (art. 157). So you may choose between forcing performance or rescinding.
Yes, as a rule you must notify him first: compensation is due only after the debtor has been put on notice, unless otherwise provided (art. 218), and notice is given by a warning (indhar) or its equivalent, and may be sent by post as set out in the Code of Procedure (art. 219).
Note the judge’s powers: the judge may grant the debtor a grace period if circumstances require, and may refuse rescission if what the debtor failed to perform is minor relative to the obligation as a whole (art. 157). If rescission is ordered, the parties are restored to the position they were in before the contract (art. 160).
This is general legal information, not legal advice. For advice on your specific situation, consult a lawyer licensed in Egypt.