Having trouble getting through on the telephone to the District of Columbia government about a consumer complaint, welfare payments, a liquor license or an insurance question?

Or a discrimination complaint or drug addiction treatment or mental health assistance or government contract information?

Or . . . well.

The problem is that more than 200 of the 1,975 telephone listings for city government offices in the C&P Telephone Co. directory are incorrect.

They are incorrect because the city government is converting from its old electro-mechanical telephone system to a Centrex system with entirely new numbers.

Some agencies such as courts, libraries, schools and the City Council converted more than a year ago, so their new Centrex numbers appear in the current C&P directory, published last May.

Portions of at least 10 agencies, including the sprawling Department of Human Resources with its thousands of phones and extensions across the city, converted to Centrex more recently, and their uncorrected numbers are still in the phone book.

D.C. government operators are supposed to intercept all calls on the old numbers and give out the new Centrex numbers, but often the operators are so swamped that they cannot get to them all.

The result: your call rings and rings and rings until you give up, get a busy signal or, sometimes, get nothing - no ring, no busy signal, no dial tone, nothing.

"It used to be a lot worse," says T.J. (Dutch) Behrens, keeper of the city government's 25,000 to 30,000 telephones and the man in charge of the mammoth Centrex conversion.

Five years ago when the conversion was being planned, he said, "There were 35,000 busy signals a day on the District government's main information number." That is 628-6000.

Even today, he said, the 18 or 20 switchboard operators working at peak periods of the day sometimes must juggle 50 to 100 calls simultaneously. "That's why there are delays sometimes. Those operators are very busy," he said.

"The old system was totally overloaded," Behrens said. The phased year-by-year conversion to Centrex is now about half complete, he said, "and as we put more people in Centrex, we reduce the number on the old system . . . We get very few busy signals now."

The other good news is that the phone company is scheduled to start distributing on Monday new D.C. directories that should contain updated numbers for the newly converted agencies.

The problem will begin again, however, because several large city government agencies, such as the police, transportation and environmental services departments, are not scheduled for conversion to Centrex until later this year, so their new numbers thus will not be in the new phone book.

Behrens, whose officials title is chief, telephone management division, D.C.

Department of General Services, says the conversion process is cumbersome, complicated and impossible to administer smoothly.

The job required physical replacement of the city's three old PBX (private branch exchange) switchboards with a single Centrex console in the Municipal Center at 300 Indiana Ave. NW and a "one-for-one" conversion of numbers on 12,000 dialable lines and the 25,000 to 30,000 phones connected to them, Behrens said.

The conversion, scheduled for completion early next year, will cost about $240,000, but the city will recover that amount within the first year of operation, he said, because of an estimated annual saying of $250,000 in leasing fees to C&P.

The crew of about 35 switchboard operators also will be reduced eventually to about 15 because of increased automatic features in the Centrex system, he said. The work force reduction will be attrition, not layoffs, he said.

A chief advantage of Centrex, in addition to financial savings, Behrens said, is that operators will be able to transfer callers anywhere within the government system, rather than requiring the caller to hang up and dial a new number as is often the case now.

Gone will be the familiar city government numbers beginning with 626, 628 and 629. They will be replaced by six new three-digit prefixes: 724 and 727 for downtown and new Southwest, 767 for far Southeast, 576 for Northeast, 673 for near Northwest and 282 for far Northwest.

Hundreds of city government phone listings in the current C&P directory use these new prefixes where conversions have been completed.

The police, fire and rescue emergency number - 911 - will remain the same after conversion.

For now, there are two D.C. government general information numbers: 628-6000, the old PBX number, and 727-1000, the new Centrex information number. When conversion is completed, only the 727-1000 numbers will function.