Often, when folks are in Chapter 13 Bankruptcy, their income will change and they find themselves unable to make the trustee payment. What do they do then ?
You would immediately contact your attorney who would sit down with you in the office and consider the options.
You would possibly have the option of lowering the percentage you are paying to unsecured creditors, thereby lowering your plan payment.  A motion would need to be filed by your attorney and approved by the Bankruptcy Judge.
There could also be the option of converting your Chapter 13 Bankruptcy to a Chapter 7 Bankruptcy or dismissing your Chapter 13 Bankruptcy and filing a new Chapter 7 Bankruptcy.
Your attorney will guide you in which option is best for you.
The most important thing of all is to contact your attorney immediately as soon as your income changes !