RTO rejecting fitness certificate even after fitting speed limiter

hi. I hv a commercial Vechile tempo traveller mini bus which needs a fitness certificate every year. This time I seek RTO for fitness certificate They rejected due to non limit of speed . Then I rush to the authorised service centre n hv a limit on Vechile by as the company fitting speed limiter . Then again I seek RTO for fitness then again rejected for same purpose. I personally tested the Vechile which was not exceeding limit of 80 km . After argument with the officer. Finally I hv to put the speed governor only from the agent that RTO which a unauthorised commission agent . I hv a settlement with him . I told him I hv a company fitted speed limiter . He said "we will just showoff the officer that it has been fitted I hv a good Pehchaan." As said he make my work n Vechile was certified. Then the part come of Payment. As discussed I was giving a some amount n returning the speed governor to him. He suddenly hv a u turn n said u hv to pay all amount of t