Rúɡuǒ jiē bú dào nǐ de xìn, wǒ jiù bù lái nǐ nà'ér le.
False: 如果接不到你的信,我就不来你那儿了。
Rúɡuǒ jiē bú dào nǐ de xìn, wǒ jiù bú qù nǐ nà'ér le.
True: 如果接不到你的信,我就不去你那儿了。
“来”的意思是从别处到说话人所在地。原句却是说话人由所在地向别处走,应当改“来”为“去”。
来 implies the direction from a place to wher the speaker is. In the sentnece above, the motion proceeds a way from the speaker. Thus 去 rather than 来 is the right word.