My RTTS pitcher loses velocity

[Wildbill004969_XBL]

I created my pitcher and worked my way up to 96-101 on its 4 steam fastball within two seasons. I had games where the velocity dip to 88-93 but within two games it bumps back up to 96-101. Now season playing the year 2028 the first four games it went 96-101, down to 88-93. After that, it continues to be at 88-93 the rest of the season. I added velocity diamond 4 and it did nothing. Is there something else I have to do or is there a glitch? On my player profile, it still shows 96-101 fastball, slider 88-92, etc...