Kindly help me to correct these sentences

Please look at the sentence below and advise me if they are worded correctly.

Slatted bed base supplied doesn't fit the bed. It is larger than the Bed inner slot size, so we can't place it in bed inner slot. We can only lay it flat on the bed's long rail frame without its legs. If we have a size of slatted bed base as 140 x 170 x ht 25 cm, we can install it in the bed inner slot.

Thank for your kind help on this