I swear I've got to get Fat_Mike to add this to the FAQ.
If you have a recent backup unit most of the problems are due to people grafting on headers from other games (you didn't dump it on your unit or it would work).
Tetris 3 has SRAM protection. You need to fix your smc header. The first three hex bytes of the header should be: 80 00 09
I'll place a small wager that the third byte in your header is different. Fix it with a hex editor.