Offer Letter vs Contract

Two years ago, I started an executive position whereby I was provided an offer letter to sign. Included in the offer letter is an allocated clothing allowance and benefits (medical, dental, etc) that I would receive. It states in the letter that "This offer is in no way a contract". However, a couple of things have happened: - I have not received my allocated clothing allowance for a year. My employer has changed the allotment as communicated per HR. Myself and my co-worker separately inquired with HR that the allotment was different from our offer letters and were informed that was what our boss decided. So we had no recourse after. - Last year, my employer stopped paying the corporate dental bill for at least two months. However, we still had deductions taken out of our check. I had to speak to our HR professional due to a bill that I received that was not covered per lack of benefits. She requested that they reimburse for the bill but there were no additional updates