Is it true that members of Congress get to vote on whether or not they’ll receive raises in salary, and if so, has it ever been voted down?

"Congress is required by Article I, Section 6, of the Constitution to determine its own pay. In the past, Congress periodically enacted specific legislation to alter its pay; the last time this occurred affected pay in 1991. More recently, pay has been determined pursuant to laws establishing formulas for automatic adjustments. The Ethics Reform Act of 1989 established the current automatic annual adjustment formula, which is based on changes in private sector wages as measured by the Employment Cost Index (ECI). The adjustment is automatic unless denied statutorily, although the perc entage may not exceed the percentage base pay increase for General Schedule (GS) employees. Member pay has since been frozen in two ways: (1) directly, through legislation that freezes salaries for Members but not for other federal employees, and (2) indirectly, through broader pay freeze legislation that covers Members and other specified categories of federal employees. Members of Congress last received a pay adjustment in January 2009."

Salaries of Members of Congress:

https://fas.org/sgp/crs/misc/97-1011.pdf

My previous Congresswoman turned down numerous raises.