I can't seem to beat the $5 or $6

[ghettointlectual]

I have played close to 2000 hu sng's on ft

I win at the $2 at %7 roi with more than 700 games played

I move up to the 5 a couple weeks ago and I can't seem to win anything with over 400 games I have a -3.4% roi

After that stretch I moved down played about 300 more games at $2 and now with about 200 games at the 6$ I have -7% roi
I will outline my strategy because I don't know what I am doing wrong. I have tried reviewing hand histories reading as much as I can about heads up and nothing seems to work

I raise about top 40-50% of hands on the button
I cbet if I have any piece of the flop or 6 outs or better
I shutdown going for a cheap showdown if I have 2 or 3rd pair unless I improve.

I play tight oop.
IF its limped to me I will raise to 4 or 5 bb with 88+ KJ+( AT+ (these are the hands I reraise with also) I always lead for 1/2 pot in this situation on the flop

I only call raises with small pp early on, any broadway, A7+ K9+ J9+ Q9+ 9T and 8T

That is basically how I play

What am I doing wrong?