Contradiction with Joel 1:10
Joel 2:23 speaks of the abundance provided by God, but Joel 1:10 describes the fields wasted and the land mourning due to drought and locusts.
Joel 1:10: The field is wasted, the land mourneth; for the corn is wasted: the new wine is dried up, the oil languisheth.
Contradiction with Haggai 1:11
While Joel 2:23 mentions God giving rain, Haggai 1:11 speaks of God calling for a drought on the land.
Haggai 1:11: And I called for a drought upon the land, and upon the mountains, and upon the corn, and upon the new wine, and upon the oil, and upon [that] which the ground bringeth forth, and upon men, and upon cattle, and upon all the labour of the hands.
Contradiction with Amos 4:7
Joel 2:23 promises rain from God, but Amos 4:7 describes God withholding rain from certain parts of Israel.
Amos 4:7: And also I have withholden the rain from you, when [there were] yet three months to the harvest: and I caused it to rain upon one city, and caused it not to rain upon another city: one piece was rained upon, and the piece whereupon it rained not withered.
Contradiction with Deuteronomy 28:24
Joel 2:23 talks about receiving rain in due season, whereas Deuteronomy 28:24 warns of the sky being turned into iron with no rain.
Deuteronomy 28:24: The LORD shall make the rain of thy land powder and dust: from heaven shall it come down upon thee, until thou be destroyed.
Contradiction with Isaiah 5:6
Joel 2:23 mentions God providing rain, in contrast, Isaiah 5:6 speaks of God withholding rain from a vineyard as judgment.
Isaiah 5:6: And I will lay it waste: it shall not be pruned, nor digged; but there shall come up briers and thorns: I will also command the clouds that they rain no rain upon it.