求助！产假结束前一个月，接到employment termination offer 该怎么办？

如题。我在加拿大，termination offers 8 weeks package. Due in 5 days. 理由是 performance & language. 产假前工作1年8个月。从未接到过任何warning regarding to my performance. 与直接supervisor在工作初期有过issues. Supervisor是公认的极度controlling但我都是主动协调处理，以致休产假前supervisor与我口头转述产假回来后会face more responsibilities and take over more works。休假前也明确表明了回去上班时间。期间supervisor跳槽。前段时间paid a visit to the office. 上周接到大领导要求another visit. And He gave the termination offer to me inperson and accused me for perfprmance & language problem.. 思前想后，实在觉得illegal 且unfair. 理由实在过于牵强。很着急，想fight,不只如何是好？家有2孩，这真是晴天霹雳.真诚寻求宝贵意见专业信息给些意见