B1A4 has not yet renewed their contracts with WM Entertainment.
WM Entertainment confirmed, "Today (April 23rd), is B1A4's 7th anniversary since debut. It's true that we have not yet renewed their contract. However, we've already extended their contract to the end of June. The label will do our best to renew our contract with the members."
B1A4 debuted in 2011 with their mini album 'Let's Fly'.