have 3 handsets of panasonic kx-tga400b.
their numbers (especially 1 & 2 ) are
spardioc in their dialing. may need to punch number 10-15 times before it connects.
how to repair ??
Hard to press & register numbers can be simply fixed with the replacement of an internal rubber mat unit for the entire number area. A company on Ebay sells an improved one which lasts much longer. Taking apart the telephone casing is required. So, the ease of installation reflects your capacity to open the case and properly close it at completion. (see barclay international on ebay. they are a trusted outfit.)