Legal Question in Business Law in California

No. Worst case, you should be able to collect under theories of (1) actual written contract through messaging, and/or (2) "detrimental reliance" (a promise which the promisor should reasonably expect to induce action or forbearance on the part of the promisee or a third person and which does induce such action or forbearance is binding if injustice can be avoided only by enforcement of the promise), and/or (3) "quantum meruit" (where you act pursuant to an express request for services from a person and the services rendered were intended to and did benefit that person).

Mr. Beal is right. To elaborate on his first point, your text messages may very well amount to a contract even though they are different from the kind of document the word "contract" usually brings to mind.

First, I believe that before assuming a change of management means that the client is dumping everything they were doing and abandoning all plans, you should check with (a) anyone you were dealing with that's still there, and (b) the new manager(s) in the management area where you were dealing, to see whether they know about your contract and whether they intend to abide by it. It's perhaps too soon to assume the worst. See if the new folks were aware of your deal and whether they will live up to it.

Next, approach the whole situation with an attitude that your contract is valid and enforceable. Not only can contracts be formed orally (with spoken words), they can and often are formed these days by electronic communications, including e-mails, where the use of an electronic signature often has the effect of one written with pen and ink.

California has adopted the Uniform Electronic Transactions Act, which appears in the Civil Code as sections 1633.1 through 1633.17. You may want to look it up. I also agree with the two previous answers (Mr. Beal and Mr. Hoffman).